Obesogens are chemicals that exert negative effects on your cells. You may recognize many on a list that contains bisphenol-A (BPA), parabens, flame retardants and pesticides.1 The majority are known endocrine-disrupting chemicals (EDCs) that may be sabotaging your weight loss efforts.
Other obesogens include PFASs,2 commonly found in food packaging, household cleaners, nonstick cookware, firefighting foam and stain-resistant carpets, rugs and furniture.
Exposure to this single chemical can happen through your food, indoor air and dust, drinking water and products used at home and at work. Aside from being an obesogen, according to Toxic-Free Culture, PFAS is also linked to liver and kidney toxicity, reproductive and developmental toxicity and cancer. This is just one chemical in a long list of compounds used in everyday materials.
Despite global recognition that obesity is pandemic and endless health campaigns being held to address the challenge, the trend is steadily rising. In 1960, just under 15% of the population were obese, as compared to 35% in 2005.3 This number had risen to 39.8% by 2016.4
Obesogens: Environmental Factors Contributing to Obesity
Professor Emeritus Philippa D. Darbre, from the University of Reading, U.K, is an expert in EDCs. In her book, “Endocrine Disorders and Human Health,”5 she describes the actions these chemicals take which disrupt your ability to maintain or lose weight.
The chemicals increase fat accumulation and promote the growth of fat cells, she explains. They also increase the number and size of adipose cells and alter hormones that regulate appetite. Additionally, obesogens change your metabolic rate and favor storing calories rather than burning them.
The idea was first published in 2002 by a researcher from Scotland in an obscure journal, but it caught the attention of a few scientists.6 The research began to build after a commentary on the study was published in a well-read toxicology journal.
Jerrold Heindel Ph.D., of the National Institute of Environmental Health Sciences (NIEHS), focused on the fact that toxicity testing for chemicals was conducted to see if it was related to weight loss, which is considered an effect of toxicity.
But, as reported by Newsweek, researchers “overlooked instances when the chemicals caused weight gain” — which Heindel noted is important, since “a number of chemicals caused weight gain — and at low doses,” such as the amount a fetus or infant would be exposed to.
Heindel also noted that research showed that exposing certain cells in a test tube to chemicals, including BPA, could stimulate the growth of fat cells. He wrote that if this could also happen in a living organism, “the result would be an animal [with] the tendency to become obese.”
Only two years later, the leaders of an animal study demonstrated newborn mice exposed to a hormone-mimicking compound had 36% more body fat and were 20% heavier than the mice who were used in the control, Newsweek said.
In fact, results from more recent studies have continued to support the obesogen hypothesis.7 One additional issue is the mixture of EDCs you are exposed to over a lifetime. This is where years of mapping the human genome may be of benefit.
Experimental researchers and epidemiologists are analyzing levels of exposure to single and multiple chemicals using exposome studies. According to the CDC8 an exposome is “defined as the measure of all the exposures of an individual in a lifetime and how those exposures relate to health.” Researchers hope:
“This will inform and guide future laboratory and epidemiological approaches that will overcome the current limitations. In turn, this will allow us to assess the costs to society of EDC and obesogen exposure more accurately. In an optimistic view, this information might influence policy makers to take appropriate steps to protect the public health.”
Early Life Exposure to Trace Chemicals and Infant Obesity
Bruce Blumberg, Ph.D., was at the University of California Irvine when he read the 2002 published paper. He was not impressed by the hypothesis, however, so he decided to conduct his own experiments. By 2006 he had designed and executed an animal study in which pregnant mice were fed an endocrine-disrupting chemical known to enter the food chain and drinking water.
The offspring were born with more fat cells, and by adulthood were up to 20% heavier than those not exposed. Through genetic testing, he discovered the chemical activated a receptor to change the direction of fibroblast development. The change was so reliable that Blumberg coined the term “obesogen” to describe the effect.
This challenges the long-held belief that weight gain and loss are based solely on calories eaten versus calories burned. But, as intermittent fasting and ketogenic nutrition plans demonstrate, there is a difference in how efficiently calories might be burned.
In another demonstration of factors affecting weight loss and gain, results from an animal study9 showed what most night shift workers likely know instinctively: that eating food at night packs on more pounds than eating the same amount during the day.10
The authors of a literature review published in 2018 analyzed existing surveys and animal studies and found that the “most important sources of exposure to obesogens indoors are diet, house dust and everyday products such as cleaning chemicals, kitchenware or cosmetics.”11
This ubiquitous exposure pattern is at the heart of prenatal and infant exposure to chemicals with the ability to change cell function and slow metabolic rates. The infant population over the past several decades has begun to grow.
CDC data show that from 1971 to 1974 as plastics became more popular and the use of endocrine-disrupting chemicals was growing, only 6.7% of infants ages 12 to 24 months were obese.12 In the coming years the percentage of obese infants ages 6 to 24 months took an upward trajectory.
While the growth rate has varied, by 2000 10.4% of all infants were obese and in 2016 it was 9.9%. In a retrospective chart review13 of infant growth patterns, researchers found there were significantly different patterns that became evident as early as 2 to 6 months. The data showed a correlation between body mass index values at 4 months and 5 years.
Later support for these findings came from the University of Virginia, which showed that babies who are born overweight are likely to remain overweight.14 Further findings from animal research indicate that weight differences triggered by obesogenic chemicals may increase the potential for obesity in the following four generations.15
The Rising Challenge of Weight Management
The challenge of obesity and weight management presents a mental, emotional and financial burden. Being overweight or obese can increase the risk of a significant number of health challenges, including certain cancers, sleep apnea, heart disease and Type 2 diabetes.16 During pregnancy, it can raise blood sugar and blood pressure, resulting in an increased risk for cesarean delivery.
The effects can be long-lasting on individuals and communities.17 In those younger than 70, only tobacco is responsible for a greater number of deaths each year. Individuals who are overweight or obese may also suffer from discrimination, a lower quality of life and an increased risk of depression.
Using data from different states in America,18 one research team estimates the percentage of health care spending devoted to obesity rose from 6.13% in 2001 to 7.91% in 2015. This represents a 29% increase in spending for obesity-related health conditions.
Using BMI to assess your health risks may not give you the information you need to make safe life choices. The flaw with BMI is that it uses total weight to determine whether you’re overweight when it’s the total amount of body fat that represents the greater risk to your health.
By the same token, assuming you’re healthy, if you are within normal BMI limits is not an accurate assessment. For instance, an athlete or out-of-shape individual may have the same BMI or a muscular person could be categorized as overweight or obese when the only measurements used are weight and height.
Instead, your waist-to-hip ratio is a more reliable indicator of your future disease risk. A higher ratio suggests you have more visceral fat — the fat accumulation around your internal organs — which is far more hazardous than subcutaneous fat located just under your skin.
To determine your waist-to-hip ratio, get a tape measure and record your waist and hip circumference. Then divide your waist circumference by your hip circumference and compare the ratio to the values in the table below.
0.96 – 0.99
0.81 – 0.84
Where Are Obesogens at Home?
The increasing number of chemicals in your environment and diet are likely contributing to the obesity epidemic. There are some common places you can find these in your home including:19,20
- Tap water — Pesticides make their way into the tap water, the primary of which is atrazine. Although it’s been banned in Europe, it’s continued to be used in the US. Another is tributyltin (TBT), a fungicide that stimulates fat cell production. This is found in vinyl products and a preservative in textiles and carpet.
- BPA and BPA replacement chemicals — These are infused in plastics and line many cans. They may increase insulin resistance.
- Nonstick coatings — PFOAs are used to create a nonstick barrier on luggage, carpet, Teflon, backpacks and clothing. It’s also found on food packaging, such as microwave popcorn bags.
- Flame-retardant chemicals — Some, like PCBs were banned in the U.S. but remain in the food supply. Replacement chemicals, such as PBDEs, have similar effects on the endocrine system. They can be found in treated carpeting and furniture, textiles, electronics and cars.
Commonsense Approach to Reducing Your Risk
Unfortunately, the number of places where you may be exposed to obesogens continues to grow. However, while troubling, you can take specific common sense steps to reduce your risk of exposure, as I’ve mentioned in numerous previous articles. Note that some endocrine disrupters are not strictly obesogens, but they do have an effect on your ability to manage your weight.
Avoid pesticides — Eat organic, non-GMO produce and grass fed, humanely raised meat and dairy products. Don’t use pesticides on your lawn, and always remove your shoes when you enter your house.
Get rid of all nonstick and fire retardant chemicals — Nonstick cookware releases chemicals when heated. Instead, cook with ceramic or glass. Purchase mattresses, carpet and furniture that are not treated with fire-retardant chemicals.
Avoid packaged food — Eliminate canned food products, microwave popcorn and take-out containers. Avoid buying processed and packaged foods as they may contain high fructose corn syrup, artificial sweeteners, pesticides and other obesogens. Artificial sweeteners can also be found in gum, soda and pancake syrup.
Avoid vinyl and plastic — Use a cloth shower curtain that can be machine washed. These stay cleaner and last longer than vinyl. Replace luggage and backpacks with products made of organic blend canvas. Use glass to store your food and reusable storage bags at home and to bring food home from the grocery store.
Filter your water — The number of toxins in tap water makes filtering a necessity. Find out more at “Why Filtering Your Water Is a Necessity.”
Use minimal antibiotics — You may be able to prevent most reasons for antibiotics by supporting a healthy gut bacterium and using natural remedies. Antibiotics alter your gut microbiome, which influences weight management for adults and children.