The food industry insists America’s obesity crisis can be chalked up to simple math – people eat too much and exercise too little.
Nutrition and physical activity, along with genetics, do play a pivotal role in weight management and disease development, but scientists recently asked: Can chemicals found in everything from food and cosmetics to drugs and carpets make it easier for our bodies to build fat?
The answer, according to a series of peer-reviewed studies, is that the same chemicals that make our food more delicious and are used in its packaging, make our cosmetics last longer, and make our carpets and clothes stain-resistant are likely also increasing our chances of becoming overweight or obese.
Many of these chemicals – called “obesogens” by scientists – alter hormones and metabolism in subtle ways that ultimately make us gain more weight. Obesogens can increase the production of fat cells, change their shape and size, and interact with processes that regulate our appetite and sense of feeling full after a meal.
Importantly, obesogens may interact with genetics, nutrition and other environmental conditions, like sleep, exercise and stress, that together influence weight and metabolism.
Besides contributing to obesity development, many of these chemicals have far-reaching health effects, like impacts on the developing brain, the reproductive system and the immune system.
And many obesogens – including the toxic “forever chemicals” known as PFAS, BPA and its replacements, phthalates and pesticides like imidacloprid, chlorpyrifos and glyphosate – wind up in our food, especially processed and packaged food.
Other common obesogens include the chemicals in flame retardants, household cleaners and sunscreens. Indoor and outdoor environmental contaminants, like air pollution and cigarette smoke, can also act as obesogens. Overall, about 50 chemicals or classes of chemicals have been classified as obesogens, according to the new studies, based mostly on research in laboratory animals, with some evidence of health effects in humans. (See table.)
Common obesogens and where they are found
|
Chemical |
Product |
|
BPA, BPS |
Food packaging, thermal paper (receipts), food and storage containers, especially cans |
|
Persistent organic pollutants; dioxin and PCBs |
Air pollution, food, especially animal products |
|
Upholstered furniture, dust, carpet and carpet padding, vehicles, baby clothing, baby products like nap mats, kitchen appliances, bed linens and electronics |
|
|
Food additives; fructose, high-fructose corn syrup, artificial sweeteners; emulsifiers, BHA, MSG |
Processed foods and drinks, soda |
|
Heavy metals (arsenic, cadmium, lead) |
Food and baby food, cosmetics and personal care products, drinking water |
|
Parabens |
Preservatives in food, paper products, personal care products and pharmaceutical products |
|
Pesticides; DDT/DDE, glyphosate, chlorpyrifos,* imidacloprid, permethrin, atrazine, triflumizole |
Conventional fruits and vegetables, animal products (DDT/DDE), drinking water (atrazine) |
|
PFAS |
Food and storage containers, cookware, stain- and water-repellant clothing and other consumer products, dust, water food packaging and wrappers, drinking water, toys, personal care products, medical supplies |
|
Plasticizing agent found in food packaging, cosmetics, paint, dust, medicine, flooring materials and wall coverings, and lacquers, varnishes and coatings |
|
|
Organotins such as butyltin, dibutyltin, tributyltin |
PVC stabilizers, antifungal paint used on ships (potential seafood contamination) |
|
Burning coal, oil, gas, wood, garbage and tobacco, motor vehicle exhaust, gasoline additive, grilled or charred meat or food |
a Chemicals listed in the table primarily have evidence from animal studies, studies in cells with some chemicals showing evidence in humans indicating their ability to cause fat development.
* Banned from use on food in 2021 but allowed for non-food uses.
The number of people who have overweight and obesity in the U.S. and globally continues to climb, despite our cultural obsession with diet and exercise and myriad efforts to promote healthier diets. Since the 1970s, the number of Americans with obesity has tripled, to 42 percent. Rates of obesity are increasing in kids, too – one in five children now have obesity.
And a landmark report on children’s health published by the National Institute of Environmental Health Sciences and the Environmental Protection Agency in 2017 identified environmental exposures linked to weight gain in childhood.
Exploding rate of obesity
Genetics alone can’t explain the rapid increase in obesity, scientists say. Nor can the proliferation of fast-food restaurants and other food environment changes, such as highly targeted advertising and the explosion in the variety and availability of ready-to-eat products.
Daily exposures to manufactured chemicals from food and consumer products also play a role, scientists say. The effect of these chemicals on our bodies can begin before we are born and can harm future generations.
In animal studies, chemicals like phthalates, PFAS and BPA, for instance, increase production of white adipose tissue, which are the most common fat cells under the skin or around organs. Exposure to these chemicals has also been associated with increased fat percentage or weight circumference in people, particularly children, who may have been exposed before birth or in early childhood, when the body is most susceptible to the changes caused by obesogens.
The costs of our failure to address obesity are very high. Half the deaths in our country stem from diet-related disease. High blood pressure, high cholesterol, heart disease, Type 2 diabetes and many types of cancer are all associated with obesity.
Across the country, people in communities that struggle with economic difficulties are disproportionately affected by obesity. These communities are often more likely to be located near industrial and agricultural sources of pollution, and to experience higher exposure to several chemicals implicated as obesogens.
Communities that lack equitable access to high quality, varied, healthy food, including fresh produce, often have to depend for their food needs on highly processed and ultra-processed foods, which are associated with higher rates of obesity.
What can you do to avoid obesogens?
To avoid obesogens and other harmful chemicals, use EWG’s guides to cosmetics, sunscreens, cleaners and packaged foods. Some obesogens are easy to avoid, but many don’t appear on ingredients labels – like PFAS and BPA in food packaging, pesticides and fragrance chemicals in cosmetics and cleaners. Takeout containers and fast-food wrappers may be sources of obesogens in food, so try to prepare more meals at home using fresh and unprocessed ingredients, including organic fruits and vegetables, when possible.
What can legislators do to address obesogens?
State legislators have banned multiple chemicals, some of which may be obesogens, from cosmetics, but more must be done to eliminate these chemicals from everyday products like food and consumer products.
Congress should provide more funding to agencies like the EPA and the Food and Drug Administration to review obesogens’ health impacts and close the loopholes that allow chemical companies, not the FDA, to decide which chemicals in food and cosmetics are safe.
What can the Biden administration do to address obesogens?
In September, the Biden administration will hold a conference on hunger and nutrition. President Joe Biden’s FDA does not have to wait for Congress to act to close the loopholes that allow harmful chemicals, like obesogens, into our food and household products without adequate safety reviews. What’s more, Biden could reprogram EPA funds to accelerate review of chemicals in consumer products subject to agency review.
