BPA to Z

Exposure to BPA in the womb or during early life-- key periods of susceptibility-- appears to increase the risk of developing diabetes or obesity later in life.

Laboratory studies on animals or cells show that BPA exposures can cause biological effects related to diabetes/obesity, and have helped to identify the key periods of susceptibility and the mechanisms involved. These studies show that exposure to BPA during early development can lead to diabetes/obesity-related effects not only in first generation offspring, but also in later generations.

An expert panel of scientists has estimated that prenatal BPA exposure has a 20 - 69% probability of causing 42,400 cases of childhood obesity in the European Union, with associated lifetime costs of €1.54 billion (Legler et al. 2015). Estimated global costs of bisphenol- attributable diabetes, obesity, and metabolic syndrome were expected to exceed $1.1 trillion USD in 2024; 76% is attributed to BPS and BPF instead of BPA (Jaskulak and Zorena. 2025). 

Studies have also found links between BPA exposure and the risk of diabetes complications.

Yet the U.S. FDA still says that BPA is safe, despite "overwhelming evidence of harm." (vom Saal and Vandenberg 2020; vom Saal et al. 2024). The European Food Safety Authority (EFSA) has proposed lowering the "safe" level of BPA such that would essentially ban it from food packaging and consumer products. Scientists support this effort (Zoeller et al. 2023), but will the politicians? 

The Details

Reviews of BPA/Bisphenols and Diabetes/Obesity

A review discusses the variety of mechanisms by which BPA affects pancreatic islets, at both high and low doses (Banerjee et al. 2022); significant for any type of diabetes.

Type 1 Diabetes and Autoimmunity

A review of human and animal studies show an association between type 1 diabetes and some endocrine disrupting chemicals, including BPA and BPS (Keskesiadou et al. 2024).  

A review of BPA and autoimmune diseases finds that "Data from animal models provided consistent evidence highlighting the role of BPA in the pathogenesis, exacerbation and perpetuation of various autoimmune phenomena including ... insulitis in type 1 diabetes mellitus." (Sharif et al. 2021).

Another review on autoimmunity finds that BPA has been found to affect the immune system, leading to the development of autoimmunity, and that BPA has been found to play a role in the pathogenesis of systemic and organ-specific autoimmune diseases, including type 1 diabetes (Lazurova et al. 2021). 

A review of BPA, its substitutes, and the immune system finds that these chemicals may affect the risk of autoimmunity, as well as disrupt the human microbiome (Kodila et al. 2023).

Type 2 Diabetes and Obesity

An article summarizes evidence that finds that "there is sufficient evidence to suggest that bisphenols, a group of common chemicals found in plastics, may contribute to an increased risk of obesity and diabetes in human cohorts." (Nadal, 2025).  

A review finds that "there is sufficient evidence to show that BPA is a risk factor in the development of obesity." (García García et al. 2024).

A systematic review of 13 studies on prenatal BPA exposure and offspring obesity finds that BPA exposure increases the risk of obesity in offspring (Guo et al. 2024).

A review finds BPA in food is linked to early-onset obesity (Calcaterra et al. 2024).

A meta-analysis found BPA was associated with a higher risk of abdominal obesity, but not with other aspects of metabolic syndrome (Xiao et al. 2024). 

A review finds that the weight of evidence points towards the contribution of bisphenols in the development of obesity and associated disorders, and goes on to discuss the mechanisms involved (Dalamaga et al. 2024).

A systematic review and meta-analysis (albeit a crappy one) found that maternal exposure to BPA was associated with higher BMI and waist circumference in children (Rahimlou et al. 2024). 

A review finds BPA is linked to diabetes, obesity, and related diseases, and discusses the mechanisms involved (Kang et al. 2023).

A review of BPA substitutes like BPS, BPF, and BPAF found that, like BPA,  they also act as obesogens (Varghese and Hall, 2023).

A review finds that the substitutes for BPA (and phthalates) show similar effects on fat cells as the original chemicals, and contribute to metabolic disease (Warger et al. 2023).

A review finds that developmental exposure to BPS and BPF is linked to various metabolic disorders, including diabetes, obesity, and fatty liver (Algonaiman 2023).

A meta-analysis of BPA substitutes found a positive relationship between diabetes and BPS, BPF and BPAF, which was only statistically significant with BPS (Moreno-Gómez-Toledano et al. 2023).

A review finds that laboratory and human studies show that BPA and other food contaminants have a role in the development and progression of diabetes (Milanović et al. 2023).

A review finds that human studies show that exposure to bisphenols (not just BPA, and also phthalates) is associated with an increased risk of diabetes. Animal studies show that treatment with doses within the range of human exposure decrease insulin sensitivity and glucose tolerance, and affect beta cell mass and insulin levels (Martinez-Pinna et al. 2023). 

A review find BPA can contribute to obesity via inflammation (González-Casanova et al. 2023).

A review on BPS and BPF concludes that exposure to BPS or BPF may promote the development of obesity and diabetes, and that BPS may promote worse obesogenic effects than BPA (Alharbi et al. 2022). 

A review finds that BPA is an obesogen and can cause metabolic syndrome (Maniradhan and Calivarathan, 2022).

A review found that prenatal exposure to low levels of BPA was associated with altered metabolism in childhood and an increased risk of diabetes and obesity in adulthood (Abulehia et al. 2022).

Reviews of bisphenols (including BPA substitutes) and obesity find that they may be involved in cardiovascular disease as well as obesity (Callaghan et al. 2021; Lucas et al. 2022).

A meta-analysis of 9 studies found that children and adolescents with higher BPA exposure have a higher risk of overweight/obesity (Wu et al. 2022).

A review concludes that BPA exposure is a risk factor for the development of diabetes and obesity (Pérez-Bermejo et al. 2021).

A review concludes that exposure to BPA is associated with obesity development (Boudalia et al. 2021).  

A systematic review and meta-analysis of 10 human studies found  that each 1-ng/mL increase in BPA level increased the risk of obesity by 11% (Wu et al. 2020).

A meta-analysis of studies involving over 32,000 people found that higher BPA levels were associated with an increased risk of overweight, obesity, and a higher waist circumference in adults (Ribeiro et al. 2020).

A meta-analysis of 16 studies found that BPA exposure is associated with a higher risk of type 2 diabetes in humans (Hwang et al. 2018).

A systematic review and meta-analysis of 33 large human studies concluded that, "there is evidence from the large body of cross-sectional studies that individuals with higher BPA concentrations are more likely to suffer from diabetes, general/abdominal obesity and hypertension than those with lower BPA concentrations.... Moreover, among the five prospective studies, 3 reported significant findings, relating BPA exposure to incident diabetes, incident coronary artery disease, and weight gain" (Rancière et al. 2015). (A review focusing just on hypertension finds that BPA has an adverse on blood pressure, depending gender, dose, and timing (Wehbe et al. 2020).)

Another review summarizes "both epidemiological evidence and in vivo experimental data that point to an association between BPA exposure and the induction of insulin resistance and/or disruption of pancreatic beta cell function and/or obesity" (Chevalier and Fénichel 2015). An additional review, of 13 studies on type 2 diabetes and BPA argues that, "chance is unlikely the plausible explanation for the observed association" between BPA exposure and type 2 diabetes (Sowlat et al. 2016).

A systematic review and two meta-analyses of 13 epidemiological studies on BPA and childhood obesity looked at associations in both directions, to see if BPA increased the risk of obesity, or if obesity affected levels of BPA. It found that the relatively high-exposed group had a significantly higher risk of childhood obesity than the relatively low-exposed group. However, the group with obesity showed no significant difference in the BPA concentration when compared to the group of normal weight. This suggests that there is possible causality between BPA exposure and childhood obesity (Kim et al. 2019).

Another review finds that "Most data support the effects of bisphenol A ... on the development obesity and type 2 diabetes mellitus. These endocrine disrupting chemicals interfere with different cell signaling pathways involved in weight and glucose homeostasis." (Stojanoska et al. 2017). An additional review finds that  "Most of the clinical observational studies in humans reveal a positive link between BPA exposure, evaluated by the measurement of urinary BPA levels, and the risk of developing type 2 diabetes mellitus. Clinical studies on humans and preclinical studies on in vivo, ex vivo, and in vitro models indicate that BPA, mostly at low doses, may have a role in increasing type 2 diabetes mellitus developmental risk, directly acting on pancreatic cells, in which BPA induces the impairment of insulin and glucagon secretion, triggers inhibition of cell growth and apoptosis, and acts on muscle, hepatic, and adipose cell function, triggering an insulin-resistant state." (Provvisiero et al. 2016). 

A review finds that "Over the last decade, an enlarging body of evidence has provided a strong support for the role of BPA in the etiology of diabetes and other metabolic disorders... Exposure to EDCs [endocrine disrupting chemicals] during early life may result in permanent adverse consequences, which increases the risk of developing chronic diseases like diabetes in adult life. In addition to that, developmental abnormalities can be transmitted from one generation to the next, thus affecting future generations." (Tudurí et al. 2018).

According to a review on BPA and insulin resistance, "The hypothesis states that unnoticed and constant exposure to this environmental chemical might potentially lead to the formation of chronic low-level endocrine disruptive state that resembles gestational insulin resistance, which might contribute to the development of diabetes. The increasing body of evidence supports the major premises of this hypothesis, as exemplified by the numerous publications examining the association of BPA and insulin resistance, both epidemiological and mechanistic. However, to what extent BPA might contribute to the development of diabetes in the modern societies still remains unknown." (Pjanic 2017). Another systematic review and meta-analysis of BPA found an association between BPA and a higher BMI and insulin resistance and (as well as with polycystic ovary syndrome (PCOS), which is linked to type 2 diabetes and obesity (Hu et al. 2018). Workers exposed to BPA tend to have higher levels of exposure; this is a concern for metabolic disease as well (Caporossi and Papaleo 2017).

For a nice (and free full text) review of the evidence linking prenatal BPA exposure to diabetes and obesity, see Alonso-Magdalena et al. 2015.

A further review concludes that BPA should be considered an obesogen (Legeay and Faure 2017). 

A systematic review and meta-analysis of 61 studies on early-life exposure to BPA and obesity-related outcomes in rodents finds that it may increase fat weight and lipid levels, especially in males, and at exposure levels below the U.S. "safe" dose (Wassenaar et al. 2017). However, another finds that, "Although vast experimental literature exists, there is limited epidemiological evidence to support the hypothesis for the obesogenic effect of BPA" (Hoepner 2019). Regarding the experimental literature, a review finds that when laboratory conditions are the same, obesity is a consistent finding in BPA studies (Rubin et al. 2019).

A review of epidemiological and laboratory studies on BPA and type 2 diabetes finds that BPA alters various aspects of beta cell metabolism; varying concentrations of BPA disrupt glucose homeostasis and pancreatic beta cell function. BPA also plays a role in the development of insulin resistance and has been linked to long-term adverse metabolic effects following fetal and perinatal exposure (Farrugia et al. 2021). Additional reviews also discuss links between BPA exposure and diabetes (e.g., Akash et al. 2020).

There are more reviews as well (e.g., Biemann et al. 2021).

Gestational Diabetes

A systematic review and meta-analysis found no association between BPA exposure and gestational diabetes or glucose tolerance during pregnancy (Taheri et al.  2021).

However, another review suggests that weight gain, insulin resistance and pancreatic beta-cell dysfunction in pregnancy may play a role in the increased risk of gestational diabetes due to BPA (Filardi et al. 2020).

Diabetes Complications

A review finds that BPA exposure may contribute to the progression of diabetes complications, including nephropathy, neuropathy, cognitive dysfunction, retinopathy, and cardiopathy (Jiang et al. 2023).

In Sum

So why is BPA still legal to use? It is beyond me. Ask the FDA. And in fact, a large study tried to address this issue with the FDA, called CLARITY-BPA. It ended up in a big mess with the various authors disagreeing with each other about the conclusions the others drew from the same data (Vandenberg et al. 2019). Meanwhile, the chemical regulators in Europe are looking closely at BPA and may be making some progress (e.g., determining that BPA is an endocrine disruptor: ANSES's Working Group on "Endocrine Disruptors," et al. 2018; Beausoleil et al. 2018a Beausoleil et al. 2018b).

A similar study by many of the same authors, also based on the Nurses Health Studies, found that women (without diabetes) with the highest levels of BPA (and some phthalate) exposure gained more weight during the 10 year follow-up period than those with lower levels of exposure (Song et al. 2014). Another long-term U.S. study found that moderate BPA levels increased the risk of diabetes development in middle aged women (there was a non-linear relationship, with the highest risk at middle instead of higher exposure levels) (Lee et al. 2021).

A longitudinal study from France found a near doubling of the risk of type 2 diabetes from BPA and BPS exposure levels (Rancière et al. 2019). For an article describing this study, see Bisphenol Exposure and Type 2 Diabetes: New Evidence for a Potential Risk Factor, published in Environmental Health Perspectives (Seltenrich 2020).

In middle-aged and elderly East Asians, BPA levels were associated with fasting glucose levels, but only in people with genetic risk of diabetes (Bi et al. 2016). A longitudinal Chinese study found that BPA exposure levels were associated with increased fasting blood sugar levels and lower beta cell function in women, but not men (Wang et al. 2019). A longitudinal study of Chinese men found an increased risk of metabolic syndrome in those with higher BPA levels, but mainly in smokers (Wu et al. 2019).

In adults over age 40 in Shanghai, China, BPA levels were associated with a higher risk of developing obesity, over a 4 year period, especially in women, individuals who were younger than 60, those of normal weight, non-smokers, non-drinkers, and those without high blood pressure (Hao et al. 2018). A further study by these authors found that high BPA exposure, especially maintained a long time period apart, was associated with higher LDL cholesterol levels and lower HDL cholesterol levels among middle-aged and elderly adults (Wang et al. 2020). Another study from China found no association between BPA levels and type 2 diabetes, with 5 years of follow-up (Shu et al. 2018). Also in China, BPA levels were associated with lower HDL cholesterol levels over a 5 year period (Li et al. 2020). In Americans who traveled to China and back, an increase in BPA levels were linked to higher triglyceride levels (Lu et al. 2022). In China, BPA levels were associated with type 2 diabetes risk (in a U-shaped pattern), and those with higher BPA levels and a higher genetic diabetes risk had higher fasting glucose levels and higher risk of type 2 diabetes as well (Wang et al. 2022). BPA was associated with total and non-HDL-cholesterol changes, and with an increased risk of high triglycerides in older Chinese people (Yao et al. 2022). 

In elderly Swedish adults, BPA levels were not associated with measures of obesity (fat mass and fat distribution) two years later. BPA levels, however, were associated with levels of the hormones adiponectin, leptin, and ghrelin, which are involved with hunger and satiety (Rönn et al. 2014). 

A longitudinal study of the elderly in South Korea found BPA levels were associated with overweight in women, but not men (Lee et al. 2015).

Belgian adults with obesity had higher levels of BPA than those who were not. Over 3, 6, and 12 months of weight loss (via either dieting or bariatric surgery), levels of BPA did not change (Geens et al. 2015).

In Mexico City, higher exposure to BPA during the second trimester was associated with an increase in oxidative stress in female offspring, and prenatal BPA exposure was associated with a decreased risk of metabolic syndrome in male offspring. Diet also played a role, sometimes contrary to ways we might expect (Zamora et al. 2022).

Longitudinal Studies in Children

In Portugal, there were associations between BPA exposure and increased blood insulin level, insulin resistance, fat mass percentage, waist circumference, and BMI in children from ages 4 to 13 (Costa et al. 2024). 

In Dutch children, total bisphenols and bisphenol A were associated with a decrease in BMI from 6 to 10 years (Silva et al. 2021).

In France, early childhood exposure to a mixture of chemicals including bisphenols was associated with higher BMI and weight at age 3, especially in boys (Ouidir et al. 2024).

BPA exposure levels in Korean pre-adolescent girls were associated with higher insulin and insulin resistance levels one year later (Lee et al. 2013). 

In Mexican girls (but not boys), BPA levels during childhood (but not in utero) was associated with skinfold thickness (Yang et al. 2017). 

In Spanish children, genetic risk affected the links between BPA and obesity (Ramírez et al. 2024).

In children from Cincinnati Ohio,  BPA concentrations were associated with lower percent body fat at age 8 and 12 years, while urinary BPS concentrations were associated with higher percent body fat at age 8 years, but not at 12 years (Gajjar et al. 2022).

In Korean children aged 6-8, higher exposure to BPS was associated with higher BMI, and both BPS and BPF with higher fat mass. BPA levels were not consistently associated, perhaps due to lower BPA levels over time (Lee et al. 2024).

Prenatal BPA exposures were associated with a lower BMI, less body fat, and less overweight/obesity in Californian girls at age 9, while current BPA levels were associated with higher BMI, obesity/overweight, waist circumference, and fat mass at that age (Harley et al. 2013). For an article describing this study, see Unclear relationship: Prenatal but not concurrent bisphenol A exposure linked to lower weight and less fat, published by Environmental Health Perspectives (Betts 2013).

In Cincinnati, Ohio, prenatal BPA exposure levels were not associated with BMI in early childhood. Children with the highest exposures, however, grew fastest between age 2 and 5 (Braun et al. 2014).

In France, fetal exposure to BPS was associated with higher infant growth (e.g., weight, BMI, etc.) at 3 and 36 months of age (Ouidir et al. 2024). Also in France, prenatal exposures to BPS  were associated with higher fat mass at age 3 (Colombini et al. 2025).

In Canada, first-trimester maternal levels of BPA were associated with adipnectin levels in male infants-- a hormone that influences a number of metabolic processes, such as blood glucose levels. These infants will be followed to see if there are any later-life effects (Ashley-Martin et al. 2014). Also in this cohort, gestational BPA levels were associated with small increases in girl's central adiposity during early childhood (Braun et al. 2019).

In Crete (Greece), while prenatal BPA levels were not consistently associated with excess weight, exposure levels in early childhood were. BPA exposure levels at age 4 were associated with a higher BMI, waist circumference and skinfold thickness (Vafeiadi et al. 2016). In Cyprus, cord blood levels of BPA were not associated with weight-related measures at birth (Dalkan et al. 2019).

In New York City, prenatal BPA levels were not associated with fat mass during childhood (age 4-9) (Buckley et al. 2016). However a different New York City study found that prenatal BPA levels were associated with fat mass during childhood, as well as percent body fat and waist circumference at age 7 (BPA levels during childhood were not associated with any of these outcomes) (Hoepner et al. 2016).  Another NYC study found that fetal exposure to BPA and total bisphenols (and phthalates) was associated with higher weight in early childhood (Blaauwendraad et al. 2024).  

In Korea, maternal BPA levels were associated with epigenetic changes in the offspring at age 2 (but not later in childhood). These changes were in genes linked to obesity (Choi et al. 2020).

A Korean study found that maternal BPA levels were associated with higher diastolic blood pressure in children at age 4 (Bae et al. 2017). Another found that prenatal exposure to BPA was associated with lower growth in the womb, and higher growth during early childhood (Lee et al. 2018). In Japan, maternal BPA and various phthalate levels were associated with lower leptin and BPA with higher adiponectin levels in cord blood (Minatoya et al. 2018). 

In China, breastmilk levels of BPA were associated with lower weight and length gain in infants (Jin et al. 2019). Also in China, prenatal exposure to BPA was associated with a higher waist circumference and the risk of central obesity in 7 year old girls (Guo et al. 2020). At age 2, Chinese girls (not boys) exposed to higher levels of BPA prenatally had higher systolic and diastolic blood pressure. In boys, medium maternal prenatal BPA level was associated with higher glucose levels. No associations were found between prenatal BPA and child BMI, skinfold thicknesses, cholesterol/triglycerides, or insulin. There were no associations between levels of BPA in the 2 year olds and any of these measurements, implying that prenatal exposure is more important (note that BPA was detectable in 98.2% of mothers prenatally and 99.4% of children at age 2 years (Ouyang et al. 2020).

In China, first-trimester BPA levels were associated with infant growth and a higher BMI trajectory during infancy, risk factors for obesity later in life (Mei et al.  2025). In China, prenatal exposure to BPA and BPF were linked to BMI trajectories in the first two years of life (Xiong et al. 2023). Also in China, higher exposure to bisphenols prenatally was associated with higher overweight in infancy and higher rapid growth in infants. Associations in girls were generally driven by BPA, BPF, or BPS, while in boys mainly by BPF (Chen et al. 2024).  In China, prenatal exposure to BPS (as well as benzophenones, triclosan, and some phthalates), especially in the first trimester, was associated with a higher BMI at age 2 (Lv et al. 2024). Some of the mechanisms involved in fetal exposure to bisphenols and infant growth could involve epigenetics (Ji et al. 2025).

In Mexican children, in utero BPA levels were not associated with growth through age 14 (although phthalates were) (Yang et al. 2018). 

Epigenetics may play a role in exposures during development; epigenetic changes in growth and metabolism-related genes in infants were associated with BPA and phthalate levels in cord blood (Montrose et al. 2018). In the U.S., cells obtained from amniocentesis showed that fetuses exposed to BPA in the womb had gene expression patterns related to obesity and liver problems (Bansal et al. 2019).

In the womb, sugar is transported from the maternal to the fetal blood via glucose transporters (GLUTs). A study found that while no differences in GLUTs were detected between placentae from normal weight vs overweight mothers, there were differences in response to BPA. The placental response to BPA in overweight mothers resulted in a reduction in GLUT levels. Given the importance of glucose as a major source of nutrients and energy for the fetus, a worsening of its transport across the placenta could be detrimental to the fetal growth and development (Ermini et al. 2021).

Thus the results vary by study, with some showing that BPA may increase the risk of obesity, and others showing that BPA may decrease the risk of obesity. In either case, BPA may be able to affect growth rates, and the details and effects remain to be determined-- these effects may depend on a variety of things, such as the population studied, other environmental exposures, timing of exposure, dose of exposure, socio-economic factors, nutrition, etc. Also, many of the animal studies that find that BPA exposure leads to a higher body weight (see below) do not find that increase in body weight until the exposed animals reach puberty (Betts 2013).

In adults, BPA was associated with a higher BMI and waist circumference in both genders and in all ethnic groups (also NHANES data, from 2003-2008) (Shankar et al. 2012). Another study, based on NHANES data (from 2003-2008), found that BPA levels were associated with metabolic syndrome in adults (Teppala et al. 2012). Metabolic syndrome is a cluster of conditions associated with type 2 diabetes, sometimes preceding the disease. Some of the same authors also found (using the same data), that BPA was associated with pre-diabetes, defined as a somewhat high fasting blood glucose level or post-meal blood glucose level (not to the point of diabetes) (Sabanayagam et al. 2013). Another study, using NHANES data from 2003-2006, found that among adults, BPA levels were associated with both general obesity and central obesity (Carwile and Michels, 2011). A meta-analysis of data from six cross-sectional NHANES studies found no associations between BPA and levels of cholesterol or triglycerides (Dunder et al. 2019). Using NHANES data, researchers found an association between BPS exposure and diabetes risk, but not BPF exposure (Moreno-Gómez-Toledano et al. 2022). In NHANES, exposure to bisphenols was associated with markers of oxidative stress and inflammation that are linked to obesity (Zhou et al. 2023). In NHANES, BPA exposure was higher in people with high cholesterol/triglycerides (hyperlipidemia) than in those without, and increased the risk of death in those with hyperlipidemia (Guo et al. 2024). In NHANES, a mixture of bisphenols and phthalates was associated with a higher risk of diabetes, especially in Mexican-Americans (Hernández-Pérez et al. 2025). 

A Canadian study using a similarly designed dataset (the Canadian Health Measures Survey, a survey of the general population), found that BPA levels were associated with diabetes, glucose levels, and HbA1c levels (a measure of long-term blood glucose control) in adult men (but not women) (Tai and Chen 2016). A different study using the same dataset found that BPA levels were associated with obesity (as defined by BMI) (Do et al. 2017).

In American Indians of the South Dakota Cheyenne River Sioux tribe, BPA levels-- which were higher than in the average U.S. population-- were not associated with diabetes (Chang et al. 2019). In U.S. women from California and Hawai'i, BPA levels were not associated with metabolic syndrome (Ihenacho et al. 2023). 

In Mexican women, BPA levels were associated with a higher risk of diabetes (Murphy et al. 2019).

US and Korea

In both U.S. and Korean populations, higher BPA levels were associated with lipid profile and obesity. BPA levels were associated with decreased HDL cholesterol levels, increased triglyceride levels, and a higher risk of obesity. Higher BPS levels were positively associated with obesity, especially in US men and Korean women. Higher BPF levels were associated with lower HDL cholesterol and a higher risk of obesity in US women (Choi et al. 2021). 

Asia/Oceania

In Chinese adults who underwent bariatric surgery, inflammation in their fat tissue was associated with BPA exposure levels. BPA was also associated with a higher risk of obesity (Hong et al. 2023).

In China, bisphenol mixtures were associated with an increased type 2 diabetes risk, with BPA as the main contributor (Yang et al. 2024).  

A group of Chinese adults had average urinary BPA level was lower than in the U.S. Dividing participants into quartiles of BPA exposure, the risk of diabetes was higher in people in the second and fourth quartiles of exposure, but not the third. The overall trend was not significant (Ning et al. 2011). However, since BPA is an endocrine disruptor, a linear association would not necessarily be expected. Another study from China also found non-linear associations between type 2 diabetes and BPA, as well as with the sum of bisphenols. It also found that BPAF and BPS concentrations were positively associated with T2DM (Duan et al. 2018).

In Chinese adults over 40 living in Shanghai, BPA levels were associated with increased insulin resistance, general obesity, and abdominal obesity (Wang T et al. 2012). In Singapore, BPA levels were associated with BMI as well as oxidative stress (Liu et al. 2018). Also in China, those who lived in electronic waste recycling areas had higher levels of BPA in their bodies, as well as higher rates of abnormal fasting blood glucose levels, compared to those who did not live in these areas (Song et al. 2019).

In China, in the human part of a study, BPA was associated with obesity, inflammation in fat tissue, and insulin resistance. In the animal part of the study, BPA promoted obesity, inflammation in fat tissue, and insulin resistance (Wang et al. 2023). BPA levels were associated with lower HDL cholesterol levels, in people with certain genetic backgrounds (He et al. 2023). In China, BPA and PBAF were associated with lower HDL cholesterol levels (Wei et al. 2024).

In Chinese adults, levels of 16 chemicals were measured in fat tissue. Of those, BPA was the chemical most strongly linked to a high BMI (Lu et al. 2025).  

In Taiwan, young adults with higher BPA exposure levels had higher BMI, blood pressure, and inflammation (Tsen et al. 2021).

In Korea, while the risk of diabetes was somewhat higher in adults with the highest levels of BPA, the results were not statistically significant (Kim and Park, 2013). In contrast, in Iran, the risk of diabetes was much higher in adults with the highest levels of BPA (Ahmadkhaniha et al. 2014). In Koran adults, those with higher BPA levels had a higher waist circumference and were more likely to have obesity than those with lower levels. BPA levels were associated with BMI and body fat as well (Ko et al. 2014). In South Korean women of reproductive age, BPS levels were associated with higher insulin resistance (Lee et al. 2019). A Korean study also found associations between BPA and markers of inflammation, regardless of obesity or insulin resistance (Choi et al. 2017). In Korean adults, higher BPA levels were associated with greater abdominal obesity in women, especially in postmenopausal women (Lim et al. 2020). Also in Korean adults, higher BPA levels were associated with an increased risk of both diabetes and obesity (Lee et al. 2020). BPA concentrations were positively associated with obesity in nationwide representative samples of Korean adults (Moon et al. 2021).

In Korea, exposure to EDC mixtures (phthalates, phenols, parabens, and a pesticide) is associated with higher BMI in adults and adolescents (Kim et al. 2022). 

In Thailand, BPA levels were highest in adults with diabetes than in those without diabetes, with a stronger association in men than women. Impaired fasting glucose levels were not associated with BPA (Aekplakorn et al. 2015). However a different study of Thai adults found the opposite-- that impaired fasting glucose was associated with BPA, but not type 2 diabetes (Chailurkit et al. 2017).

In India, levels of BPA were significantly higher in people with type 2 diabetes compared to controls, and positively associated with  poorer blood glucose control, insulin resistance, and inflammation (Soundararajan et al. 2019). Also in India, BPA levels were higher in people with diabetes in comparison to those without diabetes. In people with diabetes, levels of BPA were linked to higher BMI, waist circumference, and leptin levels, and with lower adiponectin levels (Jain et al. 2020). In Pakistan, BPA levels were higher in those with diabetes or obesity, and associated with higher blood glucose levels (HbA1c), higher insulin resistance, and markers of inflammation, oxidative stress, dyslipidemia, and impaired liver/kidney function (Haq et al. 2020).

A study from Samoa found no significant associations between daily BPA intake and BMI or waist circumference in mothers or children, but unlike most studies, these researchers estimated BPA exposure via diet and did not measure levels in the body directly (Heinsberg et al. 2020).

Europe

In Italian adults, BPA levels were associated with higher waist circumference, triglycerides, inflammation, glucose levels, and visceral adiposity (Savastano et al. 2015). 

In Spain, genetic background was found to play a role in the relationship between bisphenols and obesity (Ramírez et al. 2021).

A small pilot study from Cyprus found that while total BPA levels were not associated with diabetes, monochlorinated BPA levels were strongly associated with diabetes. Monochlorinated BPA is formed when chlorine-containing chemicals come in contact with BPA (Andra et al. 2015). Expanding their analysis to a larger group, and this time looking at obesity, these same authors found that an association between BMI and monochlorinated BPA that was relatively weak (Andra and Makris 2015). A study from Spain found higher levels of BPA in those with diabetes, although the difference was not statistically significant (Pastor-Belda et al. 2016).

In French adults, BPA but not BPS or BPF levels were associated with a higher risk of prediabetes and diabetes (Delepierre et al. 2023).  

In Serbia, BPA levels in women with PCOS was associated with increased metabolic risk including an increased risk of obesity, higher insulin levels, and increased insulin resistance (Milanović et al. 2020).

Middle East

In Lebanon, BPA exposure levels were associated with type 2 diabetes and metabolic syndrome (Mouneimne et al. 2017). In Saudi Arabia, numerous phenols (including BPA, BPF, parabens, etc.) had a higher risk of type 2 diabetes (Li et al. 2018). 

A Canadian study found no association between BPA levels and diabetes or blood glucose levels in children (but as mentioned above, there was an association in adult men) (Tai and Chen 2016). A Danish found even opposite associations-- that normal-weight teens and children with higher BPA levels had lower insulin levels, lower insulin resistance, lower leptin, triglyceride, and total cholesterol levels, and lower fat mass, compared with those with lower BPA levels (Carlsson et al. 2018). In Canadian children, exposure to a mixture of BPA, acrylamide, glycidamide, metals, parabens, and arsenic increased the risk of overweight or obesity (Dugandzic et al. 2024).

Higher BPA levels have been linked to higher body mass index (BMI) in Chinese schoolchildren in Shanghai, aged 8-15 (Wang HX et al. 2012). Another study of Shanghai schoolchildren found that girls aged 9-12 with the highest BPA levels (equivalent to average levels in the U.S.) had twice the risk of excess body weight (over 90th percentile) as those with the lowest exposure levels (Li et al. 2013). Also in Chinese children, higher BPA levels were associated with lower height at puberty (Wang et al. 2018). In Italian children, BPA levels were associated with BMI as well (D'Aniello et al. 2015). However, in children from India, BPA was not associated with obesity (Xue et al. 2015).

A study of U.S. children (using NHANES data from 2003-2010) found that BPA levels were associated with an increased weight-to-height ratio (WHR), a measure of central obesity. WHR is thought to be a better indicator of cardiovascular risk than BMI (Wells et al. 2014).

A small study of Ohio children aged 3-8 with overweight or obesity found that BPA levels were associated with higher insulin resistance and other metabolic differences (Khalil et al. 2014). A study of Italian children with obesity found that BPA levels were directly associated with insulin resistance, no matter the BMI. In addition, laboratory experiments showed that BPA does indeed have these effects on children's fat cells (Menale et al. 2017).

In Mexican female adolescents, BPA was associated with lipid levels (e.g. cholesterol), and the phenol 2,5 DCP was associated with a higher waist circumference (Zamora et al. 2023).

In Italy, BPA levels were associated with an increased risk of obesity in girls (Deodati et al. 2023).

In Spanish children, higher BPA levels were associated with higher BMI, increased odds of overweight/obesity, and a greater risk of abdominal obesity (Mustieles et al. 2019). Also in Spanish children, dietary exposure to phytoestrogens (found in plants like soy) and BPA were related to the risk of  obesity (as was lack of exercise) (Heras-González et al. 2019). These authors also found that BPA exposure in saliva (from dental sealants) was associated with an increased risk of overweight/obesity in children (Heras-González et al. 2022). High BPA levels from meat and eggs were associated with an increased risk of overweight and obesity in Spanish girls (Gálvez-Ontiveros et al. 2024).

In Portuguese  adolescents, higher BPA exposure was associated with higher BMI, body fat, waist circumference, and insulin/triglyceride levels (Magalhães et al.  2024).

In Iranian children and adolescents, higher BPA levels were associated with higher BMI, waist circumference, risk of obesity, systolic and diastolic blood pressure, and fasting blood sugar (Amin et al. 2018).

In Turkey, children with obesity and metabolic syndrome had significantly higher urinary BPA levels than children with obesity without metabolic syndrome, and both  groups with obesity had considerably elevated levels of urinary BPA than those without obesity (Aktağ et al. 2021).

In North Indian children and adolescents, BPA exposure levels were higher in those with obesity (Malik et al. 2021).

In Chinese children, BPS, BPAF, and bisphenol mixtures (but not BPA) were associated with increased BMI, waist circumference, and overweight/obesity in boys (Chen et al. 2023).  In 4-6 year old Chinese children, higher BPA levels were associated with higher BMI, body fat mass, and percent body fat (Guo et al. 2023), as well as obesity (Liu et al. 2024).

Other Phenols

Another phenol, 4-tert-octylphenol, was associated with lower measures of insulin, insulin resistance, β-cell function, and body mass index, and with higher levels of HDL cholesterol in youth from Taiwan (Lin et al. 2018).

Epigenetics may be involved in the effects of BPA. In rats, BPA exposure led to disturbed fasting blood glucose and glucose tolerance, causing epigenetic changes in genes involved in glucose levels (Rahmani et al. 2020). Other mechanisms may be involved as well. BPA increased body weight in zebrafish via mechanisms involving impaired glucose tolerance, oxidative stress, inflammation, and gene expression (Beler et al. 2022). 

BPA exposure may accelerate beta-cell failure in post-menopausal female mice (Oliveira et al. 2020). In older hens, BPA at the " no observable adverse effect level" (NOAEL) accelerated the process of fat formation (Li et al. 2020).

In adult mice, chronic long term exposure to BPA, TBT, and DES altered the hypothalamic circuits that control food intake and energy metabolism (Marraudino et al. 2021).

There also may be interactions with diet. Mice exposed to low doses of BPA for 30 days showed increased body weight and fat mass when fed a normal diet, but not a high-fat diet (Yang et al. 2016). Another found that BPA increased the effects of a high-fat diet, but did not affect gut microbiome after bariatric surgery in rats (Son et al. 2022). Not all studies have found harmful metabolic effects of BPA, well, as least one didn't (Ding et al. 2016), but certainly most do. In mice exposed to BPA and fed a high-fat diet, females had increased body mass, insulin level, and impaired glucose tolerance, while male mice only had impaired glucose tolerance. No change was found in mice fed a standard diet and exposed to BPA (Ma et al. 2021).

In mice, exposure to low and high doses of BPA around the time of puberty increased fat mass later in life (Yang et al. 2021).

An interesting study found that BPA levels were higher in bottled water left in the car and kept at room temperature, compared to bottled water kept in the fridge. In male rats, the storage conditions affected bodyweight, some metabolic indicators, inflammation levels, testosterone levels, and sperm quality (Abdulkareem, 2021).

In adult male zebrafish, exposure to BPA (and the flame retardant TBBPA) at concentrations commonly found in the environment led to obesity, increased appetite, and fat accumulation in the liver (Tian et al. 2021).

Rabbits exposed to BPA developed insulin resistance, fatty liver, hardening of the arteries, and heart problems (Fang et al. 2015). 

BPA is considered an environmental estrogen, because it can act similarly to the hormone estrogen. The mechanism whereby BPA promoted insulin secretion has been shown to involve estrogen receptors (Adachi et al. 2005; Soriano et al. 2012). BPA can promote insulin secretion and also insulin resistance via its estrogenic effects (Alonso-Magdalena et al. 2006), as well as fatty liver (Lv et al. 2017). In fat cells, BPA as well as other estrogenic chemicals disrupt metabolism, at the dose encountered in people today (Tsou et al. 2017).

BPA may have other effects related to diabetes as well. Adult male mice exposed to the supposed "safe" dose of BPA for 2 weeks had impaired glucose sensing in their liver. Glucose sensing is important because it is the way the body tells what the blood sugar level is, and how to react. Glucose sensing is impaired in people with type 2 diabetes, and we don't know why (Perreault et al. 2013). 

Both BPA and BPF at the supposedly "safe" dose disrupted intestine tissues in adult mice, causing intestinal inflammation and gut barrier dysfunction (Zhu et al. 2022). BPA and BPF also affected gut microbiota in mice (Meng et al. 2024). 

BPA caused features of fatty liver disease in mice, which was somewhat repaired after exposure ceased (Li et al. 2023). BPF can also contribute to fatty liver in mice (Fan et al. 2024).

BPA causes diabetes in fruit flies, sugar makes it worse, and both lead to kidney problems (Rani et al. 2022).  

BPA even affects fruit flies. These effects, involving the gut as well as metabolism-related tissues, involved epigenetic mechanisms, and were enhanced with a high-sugar diet (Branco and Lemos, 2014). And worms. Even the metabolism of worms are affected by BPA (García-Espiñeira et al. 2018). And fish. Fish metabolism is also affected by BPA (Guan et al. 2018), including insulin resistance (Mukherjee et al. 2020). The toxic effects of BPA on zebrafish depend on the dose: low doses induce fat deposition, while high doses cause adverse effects on inflammation and antioxidants (Sun et al. 2019). In carp, BPA exposure increased total cholesterol, LDL cholesterol, and HDL cholesterol levels, and induced oxidative stress and inflammation (Gu et al. 2021).

A number of other researchers have pursued this topic further. When researchers exposed mother rats to BPA during pregnancy and lactation, their offspring weighed more and had glucose intolerance as adults. If the offspring were fed a high-fat diet, these effects were accelerated and exacerbated: they developed obesity severe metabolic syndrome. Interestingly, these effects showed up at the lowest dose of BPA, but not the higher doses (Wei et al. 2011). Male offspring rats exposed to BPA while in the womb and through lactation had higher blood glucose levels and insulin resistance. These effects showed up earlier in life in the rats that received a higher dose, and later in life in the lower dosed rats (Song et al. 2014). Female offspring rats exposed to BPA during development also show higher glucose levels, as well as higher triglycerides and total cholesterol levels (as do their mothers, who were exposed while pregnant) (Moustafa and Ahmed 2016). BPA disturbed the normal function of the pancreas in both offspring mice and adults, with offspring showing higher susceptibility to BPA than adults (Liu et al. 2023).

When pregnant and lactating mice were exposed to high and low doses of BPA (both relevant for human exposure), the male offspring exposed to the higher BPA dose developed glucose intolerance as adults, and the female offspring exposed to the higher BPA dose were heavier, ate more food, and had more fat than the unexposed offspring, although only when they ate a high-fat diet as adults (Mackay et al. 2013). Additional studies also show that BPA may be able to affect food intake, which could have obesity-related effects (Marraudino et al. 2019). The offspring of BPA-exposed pregnant and lactating rats had higher fasting blood glucose levels and insulin levels, as well as higher body weight at birth and after weaning (Liu et al. 2012).

Rat offspring whose mothers were exposed to BPA during pregnancy and lactation developed impaired glucose tolerance (only males), and higher glucose-stimulated insulin secretion (Galyon et al. 2017). Also in rats, developmental exposure to BPA resulted in significantly increased body weight and adipose tissue, abnormal serum lipids, and lower adiponectin levels in both female and male offspring (Gao et al. 2016). And another found that fat cells held more fat in offspring (Desai et al. 2018).

Rats exposed to BPA during development showed higher body weight throughout life, an effect that was somewhat lessened in the animals fed a soy-based diet (Patisaul et al. 2014). Other studies have also found that rats exposed to low doses of BPA during development show a variety of metabolic disruption effects, including changed glucose metabolism (Tremblay-Franco et al. 2015) and increased body weight later in life (in females) (Hass et al. 2016). In mice, prenatal exposure to low doses of BPA led to faster weight gain, insulin resistance, and increased fat cell size (Zhuang et al. 2023). Some studies have found that BPA exposure during development can also lead to lower body weight and food intake later in life (Suglia et al. 2016), while others show that BPA exposure during development can cause higher body weight and food intake later in life (Stoker et al. 2019). Perhaps the different results are due to different doses or the timing of exposure. Age and sex can also influence the specific metabolic effects of BPA during development in rats (Nguyen et al. 2020). Adult female mice exposed to BPA during gestation gained more weight than unexposed controls if fed a high-fat diet, but less weight than controls on a normal diet; males showed no difference (Feighan et al. 2024). 

An extensive study designed to test how BPA can program metabolism in early life -- at levels relevant to human exposures -- exposed mice during gestation and lactation to 8 different low doses of BPA, and followed offspring for 20 weeks after weaning, with no further exposure (until mouse adulthood). The effects varied depending on sex: adult male offspring showed dose-dependent increases of body and liver weights, no effects on fat pad weights and a dose-dependent decrease in glucagon levels. Adult female offspring showed a dose-dependent decrease in body weight, liver, muscle and fat pad weights, fat cell size, lipids (fats, e.g., cholesterol levels), leptin and adiponectin levels. Physical activity was decreased in exposed males and slightly increased in exposed females. These results suggest that BPA cannot be categorically labeled an obesogen-- males showed higher body weight from exposure while females showed lower-- but that BPA does have the ability to alter metabolism later in life, following early life exposure, and that the specific effects vary by sex (van Esterik et al. 2014). The mechanisms did not appear to involve DNA methylation, an epigenetic change (van Esterik et al. 2015). Other studies, however, do find that prenatal exposure to BPA induces epigenetic changes in the fatty tissue of mice, that may be linked to later life obesity (Taylor et al. 2018). Examination of both human and laboratory evidence showed that epigenetic changes control the impact of prenatal BPA exposure on body weight in offspring by triggering fat cell development (Junge et al. 2018). Epigenetic changes in the liver caused by BPA may also be important. In rats, early-life BPA exposure causes metabolic dysfunction in adulthood and causes epigenetic changes in the developing liver which persists long after the initial exposure. Many of the affected genes remain silent until their impact on metabolism is revealed by a later life exposure to a Western-style diet (Treviño et al. 2020).

In zebrafish, parents were exposed to BPA in water. The offspring were fertilized and grew up in BPA-free water. Nevertheless, the offspring had increased abdominal fat and effects on genes related to obesity and diabetes (Zhu et al. 2023). Zebrafish embryos exposed to BPF and BPAF had higher blood glucose levels and islet dysfunction (Gyimah et al. 2024).

Certain subgroups may be more susceptible to BPA. Male mice that are light at weaning, but then experience rapid catch-up growth immediately after weaning, are more vulnerable to the metabolic effects of very low levels of BPA (Taylor et al. 2018).

We know that maternal BPA exposure disrupts metabolism, but what about paternal exposure? In a mouse study, when males were exposed to BPA after puberty, their offspring had normal body weight, body composition, and glucose tolerance. However, when fathers were exposed to BPA during gestation and lactation, their female offspring had impaired glucose tolerance (Rashid et al. 2020).

Additional studies also detail how exposure to BPA during development affects metabolism (e.g., Esteban et al. 2019; Huang et al. 2025; Long et al. 2020; Marchlewicz et al. 2021; Martínez et al. 2020; Neier et al. 2019; Nguyen et al. 2022; Pu et al. 2022; Wang et al. 2022; Yang et al. 2022; Zulkifli et al. 2022), including effects on the gut microbiome (Diamante et al. 2020; López-Moreno et al. 2025) and the gut in general (Mu et al. 2022).

BPA Affects the Development of the Pancreas

When pregnant mice were exposed to BPA, their fetuses showed altered pancreatic development. These changes may have implications for both the structure and function of the pancreas in later life (Whitehead et al. 2016).

When pregnant mice were exposed to BPA, it affected the development of the pancreas. For the first month of life, the exposed animals had higher beta cell mass, but at 4 months, beta cell mass was equal or lower than the unexposed controls. The exposed mice also had altered fasting glucose levels (García-Arévalo et al. 2016). In mice, in utero exposure to BPA caused higher blood glucose, insulin, and cholesterol levels as well as changes to the pancreatic tissue and body weight (Bano et al. 2019). BPA affects beta cell development via the estrogen receptor β (ERβ) (Boronat-Belda et al. 2020). Usually estrogen is protective to beta cells, but it appears that even though BPA is estrogenic, it is harmful to beta cells, and researchers are trying to figure out why (Babiloni-Chust et al. 2022).

In zebrafish, embryonic exposure to low levels of both BPA and BPS impaired the normal expression of pancreatic-associated genes, and caused higher glucose levels (Gyimah et al. 2021).

In fact, some authors point out that developmental exposure to BPA affects not only the pancreas but also the other organs that also derive from the endoderm, including the thyroid, liver, gut, prostate and lung (Porreca et al. 2017).

Other Phenols

Another phenol, octylphenol, when given during development, has adverse effects on fat metabolism in pregnant rats (Kim et al. 2015). In tadpoles, octylphenol exposure influenced gene expression levels related to fat digestion and absorption, and altered the structure and composition of the gut microbiome (Liu et al. 2020).

Exposure to nonylphenol during development leads to higher fasting blood glucose levels in male offspring rats, and increased body weight as well (Yang et al. 2017). Rats exposed to nonylphenol and given a high-sucrose/high-fat diet gained more weight and had glucose intolerance, higher fasting blood glucose levels, lower levels of insulin and leptin, and fewer/smaller islets (Yu et al. 2018). In zebrafish, exposure to nonylphenol affected the expression of genes associated with fatty liver, metabolism, immune response, and oxidative stress (Huff et al. 2019), and promotes weight gain when exposed during development (Kassotis et al. 2022). A high-fat diet and early life exposure to 4-nonylphenol increased body weight and had other effects, even passed to the next generation (Zhang et al. 2023). Long-term exposure to low levels of nonylphenol affected metabolism even in adult mice (Ribeiro et al.  2023). Additional studies also show nonylphenol is obesogenic (Bérubé et al. 2024).

Developmental exposure is still a problem as well (Ivry Del Moral et al. 2016; Meng et al. 2019a; Pu et al. 2017). For example, perinatal exposure to BPS may increase the risk of obesity because it interferes with cholesterol and glucose metabolism in mice offspring (Meng et al. 2019b). In male mice, prenatal BPS exposure increased fat cell size in fatty tissue and the susceptibility to high-fat diet-induced formation of fat cells in adulthood (Ahn et al. 2020). Maternal exposure to BPS also affected the gut microbiota of offspring mice as adults (Gomez et al. 2020). Post-weaning exposure to BPS caused high triglycerides and liver injury but did not affect long-term glucose control (HbA1c). PPARγ, involved in diabetes and obesity, is a target of BPS (Mornagui et al. 2023). Mice exposed to BPS in the womb had increased weight gain, higher triglyceride levels, and fatty liver (Zhang et al. 2023). Bisphenols A, S, F, and AF affect lipid metabolism of fish larvae, and target the liver and heart (Li et al. 2023).  Female mice offspring maternally exposed to BPB and BPAF had low fasting blood glucose in adulthood, with the BPAF group also having abnormal glucose tolerance (Yue et al. 2024). Developmental exposure to the BPS derivative BPSIP raised cholesterol levels in male mice (Wang et al. 2024). 

While one study of US adults did not find an association between BPS or BPF and obesity (while BPA was associated), this study did not consider exposure during development (Liu et al. 2017). In lab animals, early life exposure to BPS and BPAF have even worse glucose-related effects than BPA and BPF (Meng et al. 2018). BPAP, another substitute, can affect blood glucose levels of laboratory animals, even at low doses (Xiao et al. 2018). In fat cells, BPAF causes inflammation and affects metabolism (Chernis et al. 2019). In fat cells, BPB, BPE, BPF, BPS, and 4-CP all affected fat accumulation and leptin levels to the same extent and potencies as BPA (Ramskov Tetzlaff et al. 2019). Other studies also find that BPS has similar effects on fat cells as BPA (e.g., Peshdary et al. 2020).

Some studies from a group in China find that BPS and BPF have different effects than BPA does... for example in mice, chronic exposure to environmentally relevant concentrations of BPS exerted an unexpected hypoglycemic effect under various dietary conditions, due to lower insulin resistance and disrupted thyroid hormone levels (Guo et al. 2021). In mice fed a normal diet, BPF did not affect glucose metabolism. But in mice fed a high-fat diet, BPF "improved" glucose metabolism and reduced insulin resistance (Lv et al. 2022). As far as I can tell, other authors have not found these effects, although neither BPS nor BPF is particularly well studied in relation to diabetes. One could also argue that these "hypoglycemic effects" are not necessarily an "improvement" -- in the case of BPS, the mechanism involved disrupted thyroid signaling, which is not a good thing to have. Other authors found that adult female zebrafish treated with BPS had overeating, a decrease of serotonin in the gut, hypoglycemia and hyperlipidemia (high cholesterol/triglycerides) (Li et al. 2022).

A computerized screening tool identified numerous bisphenols (especially BTUM, BPPH, and Pergafast 201) that may be able to target diabetes-related proteins (as well as proteins related to other diseases), implying they may play a role in diabetes (Montes-Grajales et al. 2021). Omics methods also link BPS to diabetes (An et al. 2021).

According to Dr. Frederick vom Saal, a BPA researcher from the University of Missouri, "The BPS that replaced BPA is, if anything, worse because it is very environmentally persistent." Collaborative on Health and the Environment call, Dec. 2014. A study that compared them directly found that BPS is a more potent promoter of fat cell development than BPA (Ahmed and Atlas 2016). In fact, low doses of BPA, BPS, and BPF all affect fat cell development (Verbanck et al. 2017). Another bisphenol, BPAF and its metabolite BPAF-G, induced fat accumulation and increased the expression of key markers in mouse pre-fat cells (Skledar et al. 2019). 

In liver cells, four bisphenols (BPA, BPAF, BPF, and BPS) can disrupt glucose metabolism, but they appear to act through different mechanisms (Yue et al. 2019). A study of fat cells found that while BPA was more potent than BPS in its disturbance of cholesterol metabolism, their effects were similar, and both BPA and BPS exposure could lead to insulin resistance (Zeng et al. 2020). In human fat-derived stem cells, BPF and BPS both produced a linear dose-response increase in various obesogenic effects (Reina-Pérez et al. 2021). In human stem cells, low, environmentally relevant levels of BPA and BPAF increased fat formation and lipid production, whereas higher levels of BPA and BPAF decreased fat formation. All doses of tetramethyl bisphenol F (TMBPF), a food contact coating, reduced fat and lipid production, likely at least partially just killing them (Cohen et al. 2021). In fat cells, not only BPA but also four of its substitutes disrupted crucial metabolic functions and insulin signaling under low, environmentally relevant concentrations (Schaffert et al. 2021).

Researchers find that, "Because BPA substitutes such as BPS and BPF have similar structures to BPA, they appear to have similar metabolism, potencies, and action to BPA. In addition, they may pose similar potential health hazards as BPA." (Moon 2019). A data mining approach has examined health problems linked to BPS and found many, including obesity, metabolic disruption, and endocrine disruption, and identified some of potential mechanisms involved (Carvaillo et al. 2019). A review found that BPA replacement chemicals can affect the immune system, metabolic system, gut microbiome, and more, in many different species, including humans (McDonough et al. 2021).

What Happens When Fathers Are Exposed?

An interesting study exposed only the father rats to BPA, not the mothers, and looked for effects in both the fathers and offspring. The offspring did not show metabolic effects, but the fathers did. The father rats, who were exposed to the supposedly "safe" dose of BPA over a number of weeks, showed disrupted blood glucose control and pancreatic function (but not body weight). A high fat diet worsened these effects (Ding et al. 2014).

An even more interesting study found that father rats exposed to BPS before conception sired male offspring with higher body weight, increased insulin resistance, and increased insulin secretion, and glucose intolerance (the fathers themselves, and female offspring, were not affected, and the effects occurred at the lower dose but not the higher dose) (Gong et al. 2023).

How Can Early Life Exposure Lead to Effects Later in Life?

Some studies have tried to determine the specific mechanisms by which fetal and early-life BPA exposure can induce insulin resistance and diabetes later in life. For example, Ma et al. (2013) found that at 21 weeks of age, rats exposed to BPA (while in the womb and nursing) had higher insulin resistance and insulin levels than unexposed controls (just as other studies have found). None of these effects were apparent earlier in life, at 3 weeks of age. However, the researchers did find abnormal epigenetic changes that were not apparent in the controls, which suggests that these changes may play a role in later development of insulin resistance. And again, these rats were exposed to the U.S. EPA's supposed "safe" dose of BPA. Additional studies are now identifying the specific epigenetic changes that may explain BPA's effects on metabolism (Anderson et al. 2017).

Another study looked at metabolic changes in mice exposed to BPA early in life at 2 days and 3 weeks of age. Their tissues showed differences even at this early age, including in levels of glucose, that suggested BPA induced changes in whole body metabolism (Cabaton et al. 2013).

A review finds that BPA induces epigenetic changes in a variety of genes linked to effects on glucose metabolism (Rahmani et al. 2018).

Does "The Dose Make the Poison?"

Researchers exposed pregnant mice to BPA at a range of different levels, ranging from 10 times lower than the EPA's "safe" dose to 10 times above the EPA's predicted "No Adverse Effect Level (NOAEL)." They found that at doses below the NOAEL, there were significant effects in the adult male offspring (just as other studies have found), including lower glucose tolerance, increased insulin levels and insulin resistance, higher food intake, higher body weight, more abdominal fat, and more. For most of these effects, the dose-response curve was non-linear. At the highest dose studied, there were no significant effects (Angle et al. 2013). This is a very interesting study, not only because it finds significant effects at low doses, but also because the effects at low doses are worse than at high doses. That may be in part due to the way the body reacts to hormones (and BPA is a hormonally active endocrine disruptor); when the body encounters high levels of a hormone, it reduces its cellular receptors to that hormone. The authors conclude that "the dose does not make the poison," that is, that very high doses do not necessarily have a greater effect than very low doses (Angle et al. 2013).

As an example, a laboratory study that used doses of BPA below the NOAEL level found that this prenatal BPA exposure led to tens to thousands of changes in the fat, liver, and other tissues of male offspring in mice, with effects on lipid and glucose metabolism (Shu et al. 2018).

Other authors explain that BPA (and BPS) have mechanisms of action that explain why they are very potent at very low doses (Nadal et al. 2018).

Another factor is exercise-- interestingly, female mice exposed to BPA during development participated in less physical activity than controls. They also had altered metabolism of carbohydrates and fats (Johnson et al. 2015). BPA may also affect appetite. Early life exposure to BPA increased appetite peptide and reduced satiety peptide expression in a study of the stem cells of newborn rats (Desai et al. 2018).

And, losing weight may affect BPA excretion. One study found that BPA excretion increases as bariatric surgery patients lose weight. They conclude that heavier patients with insulin resistance may store more BPA in fat tissue and therefore excrete less BPA (Dambkowski et al. 2018).

Chemicals in Combination

What are the effects of mixtures of chemicals? Very few studies have been done on chemicals in combination with one another, although that is how humans are exposed. One study exposed mice -- starting from before conception -- throughout life to very low doses (at levels thought to be "safe") of a combination of chemicals commonly found in food, including phthalates, BPA, dioxin, and PCBs, and fed them a high-fat diet. As adults, compared to unexposed controls, pollutant-exposed females developed impaired glucose tolerance, and males showed liver and cholesterol effects, as well as epigenetic changes (Naville et al. 2013). The same authors subsequently fed mice a high-fat, high-sugar diet, both with and without this same low-dose mixture of chemicals. This time, the chemical-exposed females showed improvement in glucose tolerance, inflammation, and insulin resistance at 7 weeks of age, but then worsening of these factors at 12 weeks of age. Thus the chemicals cause at first an apparent improvement, then a worsening as aging takes place (as compared to the mice fed the same diet but without chemicals) (Naville et al. 2015). 

Another study of mixtures by the same authors shows that mice with lifelong exposure to low levels of this BPA, phthalates, dioxin and PCB mixture caused changes to metabolism (e.g., high triglycerides), which were slightly different than the effects of a high-fat, high-sugar diet (Labaronne et al. 2017). This exposure not only resulted in significant changes in triglyceride levels, but also on the expression levels of a variety of genes, including those relating to metabolism, especially under a standard diet. Depending on nutritional conditions and on the metabolic tissue considered, the impact of pollutants mimicked or opposed the effects of the high-fat high-sugar diet (Naville et al. 2019).

Rats exposed to BPA and DBP phthalate alone or in combination (at levels found in the environment) had islet cell immunoreactivity. The combined exposure led alpha and beta cell death, and BPA alone to alpha cell death (Morsi et al. 2022). Other studies also show that BPA and BPF can affect alpha cells (Al-Abdulla et al. 2023; Dos Santos et al. 2022).

A mixture of BPA and phthalates caused changes associated with metabolic disorders in the developing embryos of zebrafish (Dong et al. 2018). In rodents, a mixture of BPA and phthalates acted synergistically together in females and additively in males in the metabolic system (Tassinari et al. 2021). A mixture of DEHP, DBP and BPA was linked to markers of type 2 diabetes in rats, and probiotics reduced these effects (Baralić et al. 2021). Rats exposed to mixture DEHP and BPA during development developed insulin resistance and liver dysfunction (Wang et al. 2023).  

Exposure to either BPA, arsenic or their combination, induced metabolic disruption in male mice offspring, and the combined exposure exacerbated the metabolic changes induced by either BPA or arsenic alone. The combined exposure influenced both glucose tolerance and insulin tolerance, and affected the expression of genes involved in lipid and glucose metabolism (Wang et al. 2018).

In stem cells, a mixture of bisphenols induced fat accumulation; some of the effects of the mixture did not occur when the bisphenols were tested individually (Reina-Pérez et al. 2022). 

Interestingly, mixtures of other endocrine disrupting chemicals can actually affect the levels of BPA. Single doses of triclosan, parabens, phthalates, or other phenols (and a combination of all of them) raised BPA (and estrogen) levels in mice, perhaps because they interfere with enzymes that metabolize estrogen (Pollock et al. 2018). For an article about this study, see Compound Interest: Assessing the Effects of Chemical Mixtures, published in Environmental Health Perspectives (Konkel 2017).

Additional factors can also interact with BPA to influence health effects. In rats, for example, if the parents have obesity, the offspring exposed to BPA have increased cholesterol and triglyceride levels, along with higher birth weight and rapid weight gain, and the female offspring have increased insulin resistance (Dabeer et al. 2019). Also in rats, single and combined exposures to fructose and BPA had a variety of effects, including insulin resistance, which were worse with combined exposures (Lin et al. 2019). Fructose and low levels of BPA also affected fatty tissue in rats (Liu et al. 2023). BPAF and fructose affect metabolism more than each one alone (Li et al. 2025). Trans-fat also interacts with BPA to affect metabolism (Abulehia et al. 2025).

Rats exposed to BPA prenatally and trans fat postnatally had irregular islets (Abulehia et al. 2023). 

Micro- and nano-plastics may also interact with BPA. Exposing zebrafish to nanoplastics and BPA during development led to lipid metabolism disorders in two subsequent generations, and affected gut microbiota in the exposed fish (Liu et al. 2025).  

Chemicals that can interact with BPA -- both beneficially and adversely -- are critical to the health effects of BPA (reviewed by Sonavane and Gassman, 2019). Which brings us to our next topic:

Rats exposed to BPA in the womb developed obesity and adiposity, high blood sugar and insulin levels, insulin resistance, high triglycerides, and higher glucagon and free fatty acid levels. These effects were improved by magnesium lithospermate B (MLB), an active compound of Salvia miltiorrhiza (danshen/red sage) (Huang et al. 2021).

In liver cells, curcumin reduces the effects of BPA-triggered insulin resistance (Geng et al. 2017).

Crocin, a component of saffron, protected the liver from BPA-induced toxicity in rats, and reduced triglyceride levels (although BPA also caused higher glucose levels, among other things) (Vahdati Hassani et al. 2017).

BPA induced increases in triglyceride, cholesterol, and glucose levels in zebrafish, while WL15 peptide from cysteine reduced these effects (Guru and Arockiaraj,  2022).

In rats, B. forficata commercial extract has hypoglycemic properties that can minimize the diabetes-related effects of BPA (Pinafo et al. 2019).

In rats, fructose and BPA (separately and together) caused changes to the liver linked to metabolic syndrome, whereas melatonin partly counteracted these effects (Akçay et al. 2020).

In rats, BPA increased blood pressure, total cholesterol, LDL cholesterol, body fat, leptin, adiponectin, insulin, and blood glucose levels. Grape seed extract, resveratrol, or vitamin E restored these detrimental effects of BPA in some cases (Rameshrad et al. 2019). Resveratrol also protected offspring rats from the developmental effects of BPA that lead to high blood pressure (Hsu et al. 2019). Resveratrol protected rats from the metabolic effects of BPA (Akash et al. 2023). Resveratrol butyrate esters (RBE) are derivatives of resveratrol (RSV) and butyric acid and have biological activity similar to that of RSV but are more bioavailable. RBE can suppress BPA-induced obesity in female offspring rats, and improves the intestinal microbiota (Shih et al. 2021). Perinatal exposure to BPA led to weight gain, lipid accumulation, high levels of blood lipids, and deterioration of intestinal microbiota in female offspring rats. Supplementation with resveratrol butyrate esters reduced the weight gain and lipid accumulation caused by BPA, optimized the levels of blood lipids, and improved the gut microbiota (Shih et al. 2021).

In rats, probiotics almost completely eliminated the toxicity of a mixture of phthalates and BPA (Baralić et al. 2020).

The herbal medicine Asparagus officinalis (extract of asparagus) protects rats against kidney and liver damage induced by BPA (Poormoosavi et al. 2018). 

Nigella sativa oil and thymoquinone were effective against BPA-induced metabolic disorders in rats (Fadishei et al. 2020).

Interleukin-17 antibody can improve BPA-induced obesity in mice by reducing inflammation in fatty tissue (Lu et al. 2018).

Antioxidants may be able to counteract the oxidative effects of BPA (Amjad et al. 2020).

​In mice, BPA exposure caused higher body and liver weights, as well as liver damage, while vitamin D lessened these effects (Al-Griw et al. 2023). In cell studies, vitamin D also counteracted these effects of BPA (Provvisiero et al. 2024).

In rats, lycopene (found in tomatoes) helped prevent the decreased glucose tolerance and the increased insulin resistance and inflammation caused by BPA (Elgawish et al. 2020).

In mice, Korean red ginseng inhibited BPA-induced changes in lipid metabolism (Park et al. 2020).

In cells, BPA, BPS, and BPF increased fat accumulation and Nakai extract suppressed these effects (Choi et al. 2020).

In rats, BPA increased body weight, blood pressure, LDL cholesterol, total cholesterol, triglycerides, glucose, insulin, leptin, and inflammation, and lowered HDL cholesterol and adiponectin levels. Green tea extract, epigallocatechin gallate (in green tea), and vitamin E reduced these effects (Mohsenzadeh et al. 2021).

BPA promoted fat accumulation in the liver of mice, and sulforaphane, found in cruciferous vegetables, reversed those effects (Hong et al. 2023). 

Dietary bile acid and inositol supplementation were most successful in reducing the fatty liver-related effects caused by BPA, followed by allicin and resveratrol (Zhang et al. 2023).  BPF causes fatty accumulation in liver cells, and bellidifolin lessened both that accumulation as well as fatty liver disease in mice (Xue et al. 2024).  

​An extract from an orchid, Anoectochilus burmannicus ethanolic extract (ABE), was protective against the obesogenic effects of BPA and a phthalate in fat cells (Buacheen et al. 2023). 

In rats, BPA exposure increased fat tissue as well as levels of triglycerides, LDL cholesterol, coronary risk index, leptin, and body weight, and decreased adiponectin and HDL cholesterol levels. These effects were reduced by oil from seeds of a plant found in Nigeria and Cameroon, Cucumeropsis mannii (Aja et al. 2023).

Carnosic acid and rosemary extract improved the metabolic effects of BPA in mice and in fat cells (Liao et al. 2023).

Interestingly, Vitamin E actually worsened the pancreatic damage caused by BPS in rats with diabetes (Peña-Corona et al. 2023).

BPS increased triglyceride and LDL cholesterol levels in mice, and the effects were prevented by the flavonoid puerarin (Wu et al. 2023). 

EGCG, a compound found in green tea, normalized the gut microbiota changes caused by BPA, and reduced body weight, triglyceride, and total cholesterol levels in mice (Zhang et al. 2024).

Brassica juncea extract (BJE) reduced body weight, fat mass, and fat cell size in BPA-induced obese mice (Im et al. 2025). 

In Vitro Studies on Cells

Pancreatic Beta Cells

Beta cells are the cells in the pancreas that produce insulin. Studies show that BPA affects the production and activity of insulin by pancreatic beta cells. These effects have been seen in studies using human beta cells as well as mouse beta cells, at levels comparable to those humans encounter. The effects of BPA were similar in mouse and human beta cells, and were significant even at very small doses, the doses that we are exposed to in the environment, and are likely applicable to humans (Soriano et al. 2012). In rat beta cells, low levels of BPA (and other estrogenic chemicals) affect insulin secretion and disrupt beta cell function (Song et al. 2012). A study that compared BPA to other chemicals found that only BPA affected insulin secretion in mouse beta cells (Makaji et al. 2011). 

A study that aimed to determine the mechanisms by which BPA affects beta cells found that BPA suppressed cell viability and disturbed insulin secretion. Eventually, the beta cells died. The authors found that BPA affected the mitochondria in the cells, leading to these effects (Lin et al. 2013), they are also working further to delineate the exact mechanisms involved (Wei et al. 2017). BPA has also been found to damage DNA in pancreatic beta cells, in conjunction with oxidative stress (Xin et al. 2014). It also may affect beta cells by affecting ion channels (Soriano et al. 2016). For example, BPA affects calcium ion channels in beta cells, interestingly in a non-monotonic manner (Villar-Pazos et al. 2017). In fact, BPA -- at doses that humans are exposed to -- affects the genes that control sodium (as well as calcium) ion channels, which in turn control insulin secretion. The mechanisms involves estrogen receptors as well (Martinez-Pinna et al. 2019).

Low dose exposure to BPA damaged beta cells, eventually leading to their death (apoptosis) (Anastasiou et al. 2025; Carchia et al. 2015). BPA in combination with the stress of high glucose levels led to a reduced ability of beta cells to respond to damage (Carchia et al. 2015). In beta cells, exposure to low doses of BPA results in a decrease in beta cell viability and an increase in insulin levels, as well as an increase in beta cell death (Anastasiou et al. 2022). 

An interesting study found that BPA was more potent than phthalates in reducing beta cell function. Both BPA and the phthalate metabolites reduced beta cell viability after 72 hours of exposure, with BPA the most potent. Both BPA and the phthalate metabolites increased insulin secretion after 2 hours of simultaneous exposure to the chemicals and glucose, with BPA again the most potent. However, neither BPA nor phthalates affected susceptibility to beta cell death. And, unlike other studies, low level exposures did not show effects (Weldingh et al. 2017).

Low doses of BPA exacerbate the beta cell dysfunction caused by high blood glucose, implying that BPA exposure poses a risk for people with prediabetes or diabetes (Huang et al. 2024). 

Exposure to MBP, a major metabolite of BPA, significantly reduced beta cell viability, caused insulin secretion dysfunction, and induced beta cell death (Huang et al. 2021).

A modulator of the unfolded protein response rescues beta cells from the deleterious effects of BPA-- perhaps this chemical can help restore beta cell function after BPA exposure? (Daian et al. 2023). 

Long-term, high dose exposure to BPA, as well as another phenol chemical, nonylphenol, promotes insulin secretion from the pancreatic islets in rats. Nonylphenol is used in some personal care products, pesticides, detergents, and paints (Adachi et al. 2005). (Nonylphenol also promotes obesity in mice (Hao et al. 2012).) Melatonin protects against the pancreatic damage caused by nonylphenol (Tao et al. 2022).

BPA has also been found to affect another hormone (besides insulin) that is released from beta cells (the hormone is human islet amyloid polypeptide, if you really want to know). Aggregation and misfolding of this hormone can lead to beta cell death, and indeed, BPA was found to exacerbate its aggregation in beta cells (Gong et al. 2013).

Additional studies also show that BPA can affect beta cells (Chen et al. 2018), as can BPS (Ferreira Azevedo et al. 2022) and pancreatic tissue (Sun et al. 2024).

In children's fat cells, BPA promotes inflammation and the expression of genes linked to lipid metabolism, and decreases the expression of a gene linked to insulin production (Menale et al. 2015). In children's fat cells, even at the lowest exposure level, BPA activated an enzyme that promotes conversion of pre-fat cells to fat cells (adipogenesis), and also affected gene expression (Wang et al. 2013). In women's mammary fat cells, BPA caused inflammation (Cimmino et al. 2019).

Ben-Jonathan et al. (2009) reviews earlier studies of BPA's effects on fat cells. For example, BPA has been found to affect the transport of glucose in the fat cells of mice, which could have implications for the development of diabetes (Sakurai et al. 2004). BPA increases the deposition of lipids in fat cells, which could increase the likelihood of metabolic syndrome (Wada et al. 2007). BPA also promotes the development of fat cells (Masuno et al. 2002) and is linked to increased oxidative stress in fat cells in humans (Artacho-Cordón et al. 2019). BPA makes stem cells increase triglyceride levels and may support fat cell differentiation (Salehpour et al. 2020). BPA specifically promotes the development of white fat cells, and hinders brown fat cells (Chen et al. 2024).

A mixture of bisphenols caused stem cells to differentiate into more fat cells, and the mixture had additive effects. The levels were below levels seen in humans (Norgren et al. 2022).

Scientists are now working to identify the mechanisms by which BPA can affect fat cell development (Boucher et al. 2014; Lee and Park 2019; Longo et al. 2020; Xie et al. 2016). For example, BPA can promote the development of fat cells from rodent pre-fat cells even under less-than-ideal conditions (Atlas et al. 2014). BPA can also likely affect fat cell health, via additional mechanisms (Ampem et al. 2019). And BPA can have other effects on fat cells as well (Szkudelska et al. 2021). Like BPA, BPS and BPF also increase the differentiation of fat cells from pre-fat cells (Choi et al. 2021). 

BPA is also capable of acting like other hormones besides estrogen, by binding with various other hormone receptors (just like it binds with estrogen receptors) (MacKay and Abizaid 2018). For example, it can promote the formation of fat cells by activating glucocorticoid hormone receptors, which play a role in glucose metabolism (Sargis et al. 2010). In addition, exposure of human tissues to low doses of BPA inhibits the release of a hormone (adiponectin) that increases insulin sensitivity and reduces tissue inflammation. Any factor that inhibits this hormone's release could lead to insulin resistance (Hugo et al. 2008). BPA also has other effects on fat cells that may lead to insulin resistance (Dai et al. 2016).

Some compounds that are related to BPA and used as flame retardants can activate PPARγ (peroxisome proliferator-activated gamma receptor), which play a role in glucose metabolism as well as fat storage. In one study, BPA, however, did not activate PPARγ receptors Riu et al. 2011), but in others, it did (Biasiotto et al. 2016; Useini et al. 2024). For an article on the Riu study on halogenated BPA flame retardants, see Warm reception? Halogenated BPA flame retardants and PPARγ activation, published by Environmental Health Perspectives (Barrett 2011). A study of zebrafish found that developmental exposure to these compounds promotes fat accumulation in larvae and weight gain in the juvenile fish (Riu et al. 2014).

BPF also affects fat cells detrimentally (Chen et al. 2022), as do many other bisphenols (Sun et al. 2025).

Researchers are investigating the variety of mechanisms are likely involved in BPA's effect on obesity using newer methods (Lingjuan et al. 2025).

Other Cells

BPA can affect liver cells; one study found it interfered with glucose metabolism processes (Olsvik et al. 2017); another found low levels of BPA increase cholesterol levels in liver cells (Li et al. 2019). Another phenol, 4-hexylphenol, also increases fat formation in liver cells, and increases differentiation of fat cells as well (Sun et al. 2020). BPA can contribute to fatty liver, as seen in liver cells (Zhang et al. 2023), as can BPS (Lin et al. 2025) and BPB and BPC (Gill et al. 2025).

In skeletal muscle cells (which are involved in insulin resistance), BPA affects mitochondrial function and insulin resistance (Ahmed et al. 2019). BPS and BPF can also alter skeletal muscle cell proliferation and differentiation and lead to effects tied to insulin resistance (Jing et al. 2020). In muscle cells, high concentrations of BPA increase muscle glucose uptake through an estrogen receptor-related mechanism, but induce insulin resistance through another pathway (Kasongo et al. 2022). 

In intestinal cells, BPF promotes inflammation (Liu et al. 2021). Numerous bisphenols can affect gut microbiota and gut-associated immune cells (Krause et al. 2022). BPS also promotes inflammation in intestinal cells (Ao et al. 2021).

In human placental cells, BADGE and its derivatives can affect triglyceride levels (Marqueño et al. 2018). Also in placental cells, BPA can increase oxidative stress and inflammation (Arita et al. 2019). In human embryonic stem cells, BPA and six of its replacements (BPS, BPF, BPZ, BPB, BPE, and BPAF) disrupt early embryonic development and lipid metabolism (Liang et al. 2020).

BPA and other bisphenols (BPF and chlorinated BPA, ClBPA), have been found in the brain tissue of human cadavers, showing they may be able to cross the blood-brain barrier. Brain levels of these bisphenols were associated with obesity in this study (Charisiadis et al. 2018).

A cell study shows that BPS and BPF are as equally potent as BPA in inducing insulin resistance (Kulsange et al. 2024).  

And, as discussed in the type 1 diabetes section below, BPA can affect immune cells as well. In human macrophages, both BPS and BPA can activate PPARγ receptors (Gao et al. 2019).

BPA and BPS Metabolites

BPA is often thought to break down to harmless metabolites in the body. However, a study shows that these metabolites may not be harmless at all. Pre-fat cells treated with the metabolite BPA-Glucuronide (BPA-G) showed increased fat cell formation (Boucher et al. 2015). For an article describing this study, see Unexpected activity: Evidence for Obesogenicity of a BPA Metabolite, published by Environmental Health Perspectives (Nicole, 2015).

Residue of BPS, an alternative to BPA, is detected in drinking water supplies, suggesting that BPS can be chlorinated. One study identified the byproducts of the reaction of BPS with chlorine and the effects of the main byproducts on PPARγ, which is linked to obesity. The byproducts had a 2- to 4-fold enhancement in their activities on PPARγ in comparison with BPS itself (Zheng et al. 2018).

Laboratory Studies

Two studies have found that BPA exposure accelerates insulitis and diabetes development in non-obese diabetic (NOD) mice, an animal model of type 1 diabetes (Bodin et al. 2013 and Bodin et al. 2014). The first study found that long-term exposure to BPA at relatively high levels accelerated insulitis in NOD mice. The second found that exposing mothers to BPA caused their female offspring to have more severe and higher incidence of insulitis. The authors write, "In conclusion, transmaternal BPA exposure, in utero and through lactation, accelerated the spontaneous diabetes development in NOD mice. This acceleration appeared to be related to early life modulatory effects on the immune system, resulting in adverse effects later in life." (Bodin et al. 2014). The same authors found that a mixture of BPA and phthalates did not increase the effects, if anything, some of the effects of BPA were decreased (Bodin et al. 2015).

Other authors have found that BPA exposure accelerated type 1 diabetes in adult female NOD mice, but delayed it in males, and that immunomodulation was the primary mechanism (Xu et al. 2019a). These authors also found that timing was a major factor, and that the gut microbiota were also involved. Specifically, exposure to BPA increased type 1 diabetes risk in juvenile females, in conjunction with more inflammatory gut microbiota. Adult females had a trend of increased type 1 diabetes and a general increase in immune responses. However, female offspring had a reduced type 1 development and a microbiota shift towards anti-inflammation. Meanwhile in male offspring, BPA had minimal effects on immunity and type 1 (Xu et al. 2019b).

Another study, using different rodents with chemical-induced type 1, found that BPA increased diabetes incidence. The effects depended on dose, and were actually greater at lower doses in the early stages of disease, and both lower and higher doses affected disease development later on (Cetkovic-Cvrlje et al. 2017). In another study of mice with chemical-induced type 1, BPA and octylphenol helped beta cell survival, but then resulted in impaired regulation of glucose levels as well as insulin resistance (Ahn et al. 2018). An earlier study by these authors showed that BPA and octylphenol helped increase insulin secretion in these mice (Kang et al. 2014). Rats dosed with BPA had higher glucose levels and fewer islets (El-Degwi et al. 2024). 

To examine the impact of diet in BPS-treated mice in relation to hyperglycemia, development of type 1 diabetes, immunomodulation, and behavioral changes, adult male and female non-obese diabetic excluded flora (NODEF) mice were exposed to environmentally relevant doses of BPS and fed either a soy-based diet, a phytoestrogen-free diet, or a Western diet. BPS-exposed NODEF mice had sex and diet-related changes in hyperglycemia, behaviors, and immune endpoints. For example, BPS-exposed male mice fed a soy-based diet had high blood glucose levels and impaired glucose tolerance (McDonough et al. 2021).

BPA has been shown to affect the immune system of rodents in ways that may be significant for autoimmune diseases (e.g., Özaydın et al. 2018). In genetically susceptible mice, BPA enhances the production of autoantibodies. The authors conclude that BPA may be a factor in the increased incidence of autoimmune disease in humans. Both estradiol, a natural estrogen, and the estrogenic pharmaceutical diethylstilbestrol (DES) showed the same autoimmune-enhancing effects as BPA (Yurino et al. 2004). Laboratory studies also show that BPA can affect the immune system of animals (e.g., Qiu et al. 2016). Because BPA exposure can influence the immune system, BPA is considered to be an immunotoxicant (described on the autoimmunity page (Dietert and Dietert 2007) and a risk factor for autoimmune diseases (Jochmanová et al. 2015). BPA has been associated with thyroid autoimmunity in humans, for example (Chailurkit et al. 2016). 

Exposure to BPA during development may affect the risk of various immune-related diseases (Xu et al. 2016). In animals, developmental exposure to BPA causes immune system changes in offspring that are linked to autoimmune diseases, including decreasing regulatory T cells and causing inflammation (Gao et al. 2020). In mice, BPA induced the development of the autoimmune disease lupus, and mice with lupus were more susceptible to the effects of BPA (Dong et al. 2023). 

In offspring mice, BPA, BPS or BPF exposure to mothers via skin led to adverse effects on immune response in the intestine and the body that was dependent on the specific bisphenol, the dose, and the offspring's sex. The effects included changes in gut microbiota, impaired intestinal immune response, intestinal inflammation, and effects on regulatory T cells; all these effects are linked to autoimmune diseases, including type 1 diabetes (Malaisé et al. 2021).

BPA also affects adult rodents' response to infection, and patterns of immune system cells called cytokines. Rodents exposed to BPA in utero showed an increased immune response as adults, with higher levels of certain cytokines. BPA's ability to disturb cytokine production in animals could influence inflammation; cytokines are discussed further on the inflammation page. In fact, BPA, BPS, and BPAF all affect cytokine production and are immunotoxic to macrophages: BPS was the least toxic, while BPAF was the most toxic, and BPA in the middle (Chen et al. 2018). The effects of BPA on the immune system of rodents depend on the timing of the exposure as well as gender (Richter et al. 2007). Additional studies of BPA also show that developmental exposure affects the immune system (Koike et al. 2018). Oxidative stress is another mechanism likely involved in the effects of BPA on the immune system. Zebrafish embryos, a model used to screen for toxicity in the lab, show a higher immune response when exposed to BPA (and nonylphenol), involving altered immune gene expression and oxidative stress (Xu et al. 2013). Studies of other autoimmune diseases, e.g., SLE (lupus), show that BPA can induce immune signaling that may potentiate these diseases (Panchanathan et al. 2015). Another study found that the structural alterations in DNA produced by BPA may be a factor responsible for the induction of anti-DNA autoantibodies in lupus (Alhomaidan et al. 2019). Gestational exposure to BPA can promote the development of the autoimmune disease MS in animals as well (Rogers et al. 2017). BPA can also trigger neurological autoantibodies (Kharrazian and Vojdani, 2017).

Numerous types of immune cells have been found to be affected by BPA, including T cells, regulatory T cells, B cells, dendritic cells, and macrophages (reviewed in Rogers et al. 2013; also see Huang et al. 2019; Wang et al. 2024). In fact, "virtually all the major cells of the immune system" are affected by BPA, and these pathways may be one way that autoimmune diseases are promoted by BPA (Kharrazian 2014). Many of these cells are involved in inflammation and human disease, including autoimmune disease such as type 1 diabetes. BPA has been found to specifically augment the Th1 immune response, which is linked to autoimmunity (Goto et al. 2007), additionally in experiments when exposure occurs during development (Yoshino et al. 2004). Developmental exposure to BPA also affects levels of Th17 cells, also linked to autoimmunity (Luo et al. 2016). However, another study found that BPA did not activate dendritic cells (as estrogen does), so that mechanism is probably not involved (Chakhtoura et al. 2017). Also, a more detailed study measured hundreds of immune cell outcomes following developmental BPA exposure in rats, and found changes in a few dozen of them. Most of these changes were somewhat sporadic, moderate in magnitude, were not necessarily consistent over time. The authors conclude that BPA exposure may not alter immune competence in adults (Li et al. 2018a; Li et al. 2018b). Another study found that BPA activated T cells (which is linked to autoimmunity), even though the number of T cells declined (Park et al. 2022).

At low doses, exposure to BPA and BPF during development induced intestinal and systemic immune responses linked to autoimmunity and inflammation in offspring mice (Malaisé et al. 2020). All of these changes are linked to type 1 diabetes.

In mice, BPA activates the immune system, and these effects can be passed down through multiple generations (Sowers et al. 2019). 

A review of BPA and autoimmunity concludes that, "Although research at present does not directly link BPA exposure to the development of autoimmune diseases, a large body of evidence supports the pro-inflammatory effects of BPA on the immune system. Further studies are required to elucidate the role of BPA in autoimmune pathogenesis, however caution should be taken in the use of BPA containing products by those affected or genetically susceptible to developing autoimmune diseases" (Aljadeff et al. 2018).

BPA exposure can also cause insulin immunoreactive cells in the islets, and (as also described above) affect beta cell function (Ozaydin et al. 2018).

BPA Substitutes

In adult male NOD mice, BPS exposure plus a soy-based diet led to increased insulin resistance and variable blood glucose levels, while adult females had lower blood glucose levels and delayed diabetes development. The effects could partly be explained by the diet (Xu et al. 2019c). Note that one characteristic of NOD mice is that many things can delay development of diabetes in these mice-- things that do not delay diabetes in humans-- so findings of diabetes delay in NOD mice is not necessarily applicable to humans (see the Of Mice, Dogs, and Men page for more information on this issue).

A review finds that even low level BPA exposure can lead to intestinal barrier dysfunction, disrupt microbiota, and even lead to an immune system response (Zhu et al. 2023). 

In rats, early life exposure to BPA made them more susceptible to intestinal infection than those unexposed, and impaired their ability to respond to food antigens (Ménard et al. 2014). Intestinal infections and food antigens are both linked to type 1 diabetes (see the diet and the gut page). Laboratory evidence also indicates that BPA detrimentally alters gut microbiota (Javurek et al. 2016, Koestel et al. 2017; Lai et al. 2016). In mice, BPA not only affected gut microbiota, but also increased intestinal permeability (Feng et al. 2019; Feng et al. 2020; Wang et al. 2021). In rats, BPA affected gut microbiota, caused intestinal dysfunction, and higher blood glucose levels (Ambreen et al. 2019). (Changes in gut microbiota and intestinal permeability are linked to diabetes development.) Developmental exposure of mice to BPA causes gut permeability, and weakens protective gut immune function, increasing susceptibility to inflammation (Malaisé et al. 2018), as well as more widespread inflammation (Reddivari et al. 2017). The effects that BPA has on the gut precede its effects on obesity (Malaisé et al. 2017). And, BPA causes intestinal cells to absorb more cholesterol (Feng et al. 2017), has other detrimental effects directly on the intestine (Gonkowski 2020), and affects gut serotonin levels (Barra et al. 2022).

Microorganisms from the gut microbiota of children with obesity may have more BPA biodegradation potential than those of normal-weight children; I'm not entirely sure what the ramifications of this finding are, but it was unexpected (López-Moreno et al. 2022). These authors also found that gut microbiota types with the capacity to grow in BPA were differentially represented among children with different body mass indexes (Lopez-Moreno et al. 2024).  

Adult exposure to BPA affected the diversity and composition of the gut microbiota in male mice and reduced the tight junctions in the colon, resulting in dysfunction of the gut barrier (Ni et al. 2021). BPA can not only induce intestinal cell barrier dysfunction, it also reduces the viability of intestinal mucus secreting cells, also affecting the intestinal mucus barrier (Zhao et al. 2019).

BPS also affects the gut microbiota of mice, and those changes are correlated with health effects on mice, including obesity, liver fat accumulation, poor cholesterol levels (dyslipidemia), and intestinal lesions (Chi et al. 2024).

In mice, bisphenol P exposure caused weight gain and disrupted the gut microbiota (Ma et al. 2023).  

Developmental exposure to BPA as well as BPA substitutes alters the microbial structure and function of zebrafish (Catron et al. 2018). 

A study of a mouse model of multiple sclerosis (MS), another autoimmune disease, found that BPA exposure in combination with a virus had numerous effects on these mice, including an acceleration of symptoms, increased inflammation, and changes in immune-related gene expression (Brinkmeyer-Langford et al. 2014). A mouse study of immune responses to food found that BPA, BPS and BPF impaired tolerance to food and caused inflammation (Malaisé et al. 2020).

BPA and Vitamin D Levels

Does BPA influence vitamin D levels? One cross-sectional study of U.S. adults found that women with higher BPA levels have lower vitamin D levels (Johns et al. 2016). These authors also found that BPA levels were associated with an increased risk of vitamin D deficiency in pregnant women (Johns et al. 2017). In Turkish newborn babies' umbilical cord blood, BPA levels were not associated with vitamin D levels, although a lot of babies had low vitamin D levels, and most had BPA in their blood as well (Tabanli et al. 2023).

In rats, early life exposure to BPA increased urinary excretion of vitamin D and decreased its concentration in blood, especially in females (Kim et al. 2019). Giving mother mice vitamin D supplements reduces BPA-induced effects on the immune system in offspring (Wang et al. 2020). Low vitamin D levels are linked to diabetes development (see the vitamin D deficiency page). I expect these findings will encourage additional research on the topic.

Gestational Diabetes and Diabetes Following Pregnancy

BPA

BPA has been associated with an increased risk of gestational diabetes in the U.S. (Zhu et al. 2022), Canada (Soomro et al. 2024), and India (Agrawal et al. 2025) and with higher glucose levels during pregnancy in the U.S. (Bellavia et al. 2018; Chiu et al. 2017) and China (Yang et al. 2020).

However, other studies have not found associations between BPA and gestational diabetes in the U.S. (Robledo et al. 2013) or Canada (Shapiro et al. 2015). Some even found a reduced risk, in China (Fu et al. 2024; Tang et al. 2021; Wang et al. 2017) and Mexico (Martínez-Ibarra et al. 2019).

BPS

BPS has been associated with an increased risk of gestational diabetes in the U.S. (Zhu et al. 2022) and China (Tang et al. 2021), and with  higher glucose levels during pregnancy in China (Zhang et al. 2019).

But again, not all studies have found increased risks of gestational diabetes with BPS, e.g., in Canada (Soomro et al. 2024).

BPF

BPF is also linked to an increased risk of gestational diabetes, e.g., in China (Zhang et al. 2019).

Other Phenols

Alkylphenols are also associated with an increased risk of gestational diabetes (Pang et al. 2024), as is pentachlorophenol (Wen et al. 2025).

Other Outcomes During Pregnancy

Boston pregnant women had higher cholesterol levels with higher BPA exposure (Mínguez-Alarcón et al. 2022).In Europe, higher BPA levels were associated with lower blood pressure in pregnant women (Warembourg et al. 2018). In pregnant women from the Netherlands, higher bisphenol levels in early pregnancy were associated with lower weight gain during later pregnancy (Philips et al. 2020a) and higher weight gain after pregnancy (Philips et al. 2020b). In Mexican women, BPA levels during pregnancy is associated with lower weight at delivery, but then a slower rate of weight loss through the first postpartum year (Perng et al. 2020).

BPA exposure during pregnancy is associated with inflammation and oxidative stress in mothers (Ferguson et al. 2016); perhaps these mechanisms could help explain the health effects of BPA on both mother and child. 

Laboratory Studies

When pregnant mice were exposed to low and high doses of BPA, their insulin resistance increased, and glucose tolerance decreased during the pregnancy (especially those exposed to the lower doses). Four months after the birth, they had increased insulin resistance and also weighed more than the untreated control mice (without differences in food intake). Interestingly, the effects were not apparent three months after the birth, but reappeared at four months. The results suggest that BPA could contribute to the development of gestational diabetes (Alonso-Magdalena et al. 2010). Another study by the same authors found that mother mice treated with low doses of BPA during pregnancy developed glucose intolerance, increased body weight, and insulin resistance, decreased insulin secretion, reduced beta cell mass, and increased beta cell death, several months after delivery (Alonso-Magdalena et al. 2015). 

Mice exposed to a low-dose mixture of EDCs (the pesticide atrazine, BPA, PFOA, and dioxin) while pregnant later had hyperglycemia with a persistent elevation in blood glucose two hours after glucose administration in a glucose tolerance test, while these effects were not observed in mixture-exposed non-pregnant females (six months after exposure). These findings provide biological plausibility for the associations seen between chemical exposures during pregnancy and subsequent maternal diabetes and shows that pregnancy itself can play a role in the effects of chemical exposures (Merrill et al.  2021).

Diabetes Management and Complications

People with type 2 diabetes who had higher levels of BPA in their bodies had a 7-fold (!) higher risk of developing chronic kidney disease than those with lower levels. That number is from a study of Chinese adults who were followed for 6 years (Hu et al. 2015). This finding deserves some attention!

Kidney dialysis machines are a source of BPA exposure (Bacle et al. 2019). People with diabetes undergoing dialysis have measurably higher BPA levels in their blood after a single dialysis session that before the session (those with diabetes also had higher BPA levels than those without diabetes) (Neri 2016; Turgut et al. 2016). Certain dialysis membranes expose patients to higher levels of BPA than others (Bosch-Panadero et al. 2016), and certain dialysis membranes release more BPA than others (Shen et al. 2019). Hemodiafiltration may be able to reduce the  levels of BPA in people undergoing dialysis (Mas et al. 2018; Quiroga et al. 2017). See more on kidney dialysis and BPA (Cambien et al. 2023).

In a meta-analysis of data from two European cohort studies, in people with type 2 diabetes, the occurrence of heart attacks was significantly associated with BPA. Exposure to chlorinated derivatives of BPA, by-products of water chlorination, was very strongly associated with heart attacks in one of the studies but not in the other (whether these results may be explained by different water chlorination processes in France and Germany, resulting in different chlorinated BPA exposure levels, requires further investigation) (Hu et al. 2019). In India, BPA levels were higher in people with type 2 diabetes who also had vascular complications, and were associated with vascular calcification and its markers (Mohanraj et al. 2023).

Exposure to BPA may promote the development and progression of non-alcoholic fatty liver disease (NAFLD), particularly in people with type 2 diabetes (Dallio et al. 2018; Dallio et al. 2019). 

Exposure to BPA was associated with increased all-cause mortality in those with diabetic retinopathy (Zhang et al. 2025).  

BPA elimination is impaired in individuals with diabetes, obesity, or fatty liver, as shown in studies with human and mouse liver samples. The liver metabolizes BPA and leads to its elimination from the body (Yalcin et al. 2016).

In people with type 2 diabetes, BPA exposure may affect the development and normal function of cardiac cells (Liu et al. 2020).

In People Without Diabetes

Melzer et al. (2010) and Lang et al. (2008) and Cai et al. (2020) have found that BPA is associated with heart/cardiovascular disease in the general U.S. population. In fact, numerous human studies have shown that higher BPA concentrations in humans are associated with various types of cardiovascular diseases, including angina, hypertension, heart attack, and coronary and peripheral arterial disease (e.g., Aekplorn et al 2015; Han and Hong 2016, and reviewed in Gao and Wang 2014 and Fu et al. 2020). In Chinese adults, BPA is also associated with albuminuria (protein in the urine), a common complication of diabetes (Li et al. 2012). In Ohio children, BPA levels were associated with higher blood pressure and other adverse liver and metabolic changes (Khalil et al. 2014). In European children, prenatal BPA exposure is associated with higher diastolic blood pressure (Warembourg et al. 2019). In U.S. and Korean adults, BPA exposure was associated with hypertension (high blood pressure) as well (Bae et al. 2012; Shankar and Teppela, 2012), as was both BPA and BPS in Chinese adults (Jiang et al. 2019). And in those with hypertension, BPA is associated with the development of kidney disease (Hu et al. 2016). In animals, BPA exposure affects the heart muscle (Sivashanmugam et al. 2017), and exposure during development affects the development of the kidneys (Nuñez et al. 2018).

Higher nonylphenol exposure is associated with lower kidney function in humans (Chen et al. 2021).

Higher BPA and BPS exposure levels were associated with a higher risk of non-alcoholic fatty liver disease (NAFLD) in U.S. adults (Peng et al. 2022; Kim et al. 2019). The risk of NAFLD is also increased in adolescents with higher levels of BPA exposure, particularly in those of Hispanic ethnicity (Verstraete et al. 2018). In the general Korean adult population, BPA is also associated with an increased risk of NAFLD (An et al. 2021). BPF is also linked to an increased risk of NAFLD in humans, and can cause related changes in mice (Wang et al. 2023; Wang et al. 2020).

BPA is also linked to obstructive sleep apnea, common in people with diabetes, obesity, or metabolic syndrome. People with severe sleep apnea were found to have higher levels of BPA (and lower levels of vitamin D) (Erden et al. 2014).

Laboratory Studies: Complications

In animals, mice chronically exposed to BPA and a high-fat, high-cholesterol diet showed accelerated atherosclerosis as compared to control mice who ate the same diet but were not exposed to BPA. The exposed mice also had higher levels of non-HDL cholesterol than controls (Kim et al. 2014). Animal studies show that BPA causes atherosclerosis and high blood pressure in rodents (reviewed in Gao and Wang 2014, or specific studies such as Saura et al. 2014). In mice, BPA exposure during development also exacerbates atherosclerosis during adulthood (Sui et al. 2018).

Adult exposure to BPA causes fatty liver in lab animals (Sun et al. 2020; Yang et al. 2017); early-life exposure to BPA also enhances fatty liver and non-alcoholic fatty liver disease (NAFLD) in animals (Fang et al. 2022; Lin et al. 2019; Shimpi et al. 2017), especially in combination with a high fat diet (Wei et al. 2014; Strakovsky et al. 2015). Post-weaning exposure also causes NAFLD in mice (Lin et al. 2017). Fetal exposure also affects fetal development of the liver in mice (DeBenedictis et al. 2016), and exposure during development can contribute to NAFLD in the offspring of rats with obesity (Dabeer and Raisuddin, 2022). BPA's effects on the liver appear to involve mitochondrial dysfunction in liver cells (Khan et al. 2016) and oxidative stress (Vahdati Hassani et al. 2018). BPA caused fatty liver in mice, and fecal microbiota transplantation from exposed mice led to fatty liver in unexposed mice, showing that the gut microbiota is involved in this process (Hong et al. 2023). Nonylphenol also causes fatty liver disease in rats (Yu et al. 2017). And in pigs, low doses of BPA cause liver changes that are associated with diabetes and obesity in humans (Thoene et al. 2017). BPF and BPAF also affect the liver in animal studies (Meng et al. 2019), as does BPS (Li et al. 2025; Qin et al. 2020). BPF contributes to NAFLD via mitochondrial dysfunction in mice (Zhang et al. 2023).  

After 12 weeks of a high-fat diet, male mice were exposed daily to BPA along with a high-fat diet for 3 weeks. BPA amplified diet-induced alteration of key factors involved in glucose and lipid metabolism, liver triglycerides accumulation, increasing the risk of fatty liver disease (Pirozzi et al. 2020).

BPA exposure from birth through young adulthood affects heart function and blood pressure in mice, with females at greater risk (Belcher et al. 2015). It affects heart function in sheep as well (MohanKumar et al. 2017). Exposure to BPA during development affects fatty acid levels in mice (Veiga-Lopez et al. 2015). BPA also has detrimental effects on the heart (Brown et al. 2018; Gear et al. 2017; Ljunggren et al. 2016), and makes it harder for animals to recover from a heart attack (Patel et al. 2015). It is being investigated in relation to diabetic cardiomyopathy, a severe cardiovascular complication (Li et al. 2025).

BPA can also cause "brain insulin resistance" in mice, which is a condition linked to Alzheimer's disease (people with type 2 diabetes have twice the risk of developing Alzheimer's than those without diabetes) (Fang et al. 2015; Wang et al. 2017).

Animals with diabetes are more susceptible to the harmful effects of BPA on reproduction, including testicular damage (Sahu et al. 2022); rats with both diabetes and zinc deficiency are even more susceptible (Sahu and Jena, 2022). Some authors are looking into the mechanisms of BPA toxicity for people with different blood glucose levels (Li et al. 2023).

Laboratory studies show that BPA may also contribute to kidney disease (Bosch-Panadero et al. 2018). In rats with diabetes, continuous BPA exposure worsened kidney impairment, and caused heart problems as well (Wu et al. 2021).  In mice with diabetes, BPA promoted kidney alterations that resembled early diabetic kidney disease (note that the male mice exposed to both diabetes and BPA just, well, died) (Moreno-Gómez-Toledano et al. 2021).