It’s no secret rates of overweight, obesity and other metabolic diseases are skyrocketing.
And food is a big part of the problem, though not in the way you might think. It isn’t just how many calories we consume and burn. The nutritional value of food and how much it’s processed also play a role in how what we eat affects our weight.
Another likely culprit behind weight gain is the harmful chemicals in what we consume. Some of these substances, called obesogens, can contribute to weight gain and lead to obesity, in turn raising a person’s risk of heart disease and other serious health problems.
How obesogens work and can harm our health
Obesogens are chemicals that “directly or indirectly increase fat accumulation and cause obesity” by interfering with metabolism and metabolic processes, according to a recent study. Many also disrupt the hormone system, causing a wide range of health problems.
Most obesogens have been studied in animals and in cells, with some evidence of their effect on humans, and they don’t all work in the same way.
The chemicals activate cellular systems that produce more, or larger, fat cells or promote fat storage. Some can throw a wrench into the processes that stabilize our appetite and sense of fullness, or may interfere with our pleasure-driven desire to eat. Others may change our response to blood sugar and insulin. They can affect the function of several organs critical to maintaining weight and energy balance, including body fat, the brain, pancreas and liver.
Exposure to obesogens during pregnancy and early life may have an outsize role in health problems later in life.
Scientists have found evidence of about 50 of these chemicals. They can be found in many consumer products, as well as in polluted air and water. But one of the most important ways we’re exposed is by consuming contaminated food.
Harmful ingredients hiding in plain sight
Glance at the label on a package of highly processed food and you’ll see ingredients whose names you can’t pronounce, let alone understand why they’re in your food.
Studies show a link between highly processed foods – typically not very nutritious, with high levels of trans fat, sugar and sodium – and higher risk of metabolic diseases that, in turn, can lead to health problems, including heart disease, stroke and cancer, which are significant causes of preventable illness and death.
Processed foods, from fast food to some “healthy” products like protein bars and vegetarian microwave meals, often have many artificial ingredients, such as sweeteners, flavor enhancers and preservatives, some of which are obesogens.
We’re consuming more processed foods
Americans seem to have an ever-expanding appetite for these kinds of food. Between 2001 and 2018, the percent of calories American adults got from highly processed foods rose from 54 percent to 57 percent, according to one study. The percentage of kids’ total energy from these foods also jumped in that period. The result: our soaring rates of metabolic-related disease.
Adding to this trend is the fact that many Americans don’t have easy access to fresh food as an alternative to these highly processed foods. Research shows that the poorer you are in the U.S., the more likely you are to have a convenience store close by, with its bounty of highly processed foods, and less likely to have a supermarket in your neighborhood. These patterns are further compounded by racial and economic disparities.
How obesogens wind up in our food
Some obesogens occur naturally in food. One, fructose, appears on ingredient labels most often as high-fructose corn syrup and accounts for about 40 percent of sweeteners we consume. But most obesogens in food are artificial chemicals, some added intentionally, particularly in highly processed food. Others contaminate food indirectly, through packaging, residual pesticides, or legacy environmental contamination from industrial chemicals, pesticides and heavy metals.
MSG is a common flavor enhancer that shows obesogenic effects in animals.
Artificial sweeteners – particularly aspartame, sucralose and saccharin – is another obesogen found in a wide range of low-calorie and diet food and beverage products. Research suggests some may be obesogenic and others, like most chemicals, haven’t been studied enough for us to know whether they are or not.
The preservatives BHA and methyl and butyl paraben are likely obesogenic and can be found in everything from vegetable oils to processed meat and chewing gum to potato chips. Several emulsifiers are potential obesogens.
Bisphenol A, or BPA, and its replacement chemicals migrate from food packaging into food. PFOA is one of the most notorious types of the “forever chemicals” known as PFAS, used in nonstick cookware, cooking implements and food packaging like takeout containers. PFAS persist in the environment, contaminating our drinking water. Phthalates contaminate food through packaging, plastic and food handling equipment that comes into contact with food.
PCBs, once used in industrial materials like paint, varnish, plastic, pesticides and coolants, still make their way into some animal products, though they’ve been banned since 1979.
Flame retardants – used to treat clothing, bedding, electronics and children’s products, among other items – get into our waterways and eventually our food. Some have been banned, but they continue to accumulate in food, especially animal products.
Regulating or banning obesogens in food
Our focus must shift from considering overweight and obesity the result of a personal, moral failing to treating it as a result of environmental exposures and inequitable access to healthy food. This change may already be starting: Some physicians are beginning to approach obesity in their clinical practices from this perspective and looking for ways to limit exposures as an approach to weight loss.
But it’s up to the government to protect us from these chemicals: The FDA, Department of Defense and Environmental Protection Agency must ban or restrict the most pervasive and harmful food chemicals.
To make sure we face less exposure to these harmful chemicals, lawmakers and regulators must:
- Develop greater transparency in food labeling.
- Issue stronger recommendations in the Dietary Guidelines, to address other food additives, in addition to natural and artificial sweeteners, sodium and saturated fat.
- Provide more funding for programs improving accessibility and availability of healthier food options.
- Look for new ways to address environmental injustices that promote racial and ethnic disparities in exposure to obesogens in food.
In addition, the White House Conference on Hunger, Nutrition, and Health on September 28 will shine a light on obesogens, among other issues – a chance to meaningfully reduce our exposure to these chemicals.
EWG is part of a coalition of organizations that called on President Joe Biden to implement numerous changes to improve Americans’ food, nutrition and health. Two changes would protect us from ongoing exposure to obesogens:
- Closing the regulatory loophole that allows chemical companies to introduce new chemicals, some of them obesogens, into the supply chain without approval from the FDA. Many of these substances have never undergone a safety review by the FDA.
- Requiring the FDA to identify and reassess food chemicals of concern, including obesogens, already in use. The FDA doesn’t have to routinely reassess the safety of these chemicals. So substances like PFAS, BPA and phthalates remain in use long after evidence emerges linking them to harm to our metabolism and other health risks.
What you can do
Many obesogens are, at best, tough to avoid. But you can limit your exposure to chemicals added to food intentionally, especially some artificial sweeteners, preservatives and added sugars, like high-fructose corn syrup.
To reduce your exposure to harmful chemicals:
- Find out about additive names and study the labels of foods you buy to learn what you’re consuming (and can avoid).
- Eat lower on the food chain – fresh produce, beans and whole grains don’t contain food additives.
- Choose organic fruit and vegetables, when you can, to lower your exposure to pesticides. Consult EWG’s Shopper’s Guide to Pesticides in Produce™ to see which are best to eat organic and which are OK to eat non-organic, if necessary.
- Choose organic animal products – or eat less and find other protein sources instead. Antibiotics and hormones accumulate in non-organic animal products.
- Avoid plastic and grease- and waterproof food packaging. (And eat less takeout – the packaging may contain PFAS or plastic additives.)
- Use glass, ceramic or stainless steel instead of nonstick for cookware, and wood and stainless steel for cooking utensils.
- Instead of plastic, use glass, ceramic, or stainless steel containers to store and microwave food.
- For water on the go, use stainless steel bottles rather than plastic, which may leach phthalates and BPA.
- Avoid plastic labeled with code 7, which indicates the presence of BPA, or 3, which indicates PVC.
- Consult EWG’s Tap Water Database to see what’s in your water. Then see which filter is best for your own situation. Avoid bottled water – it may be no better than tap water, and the plastic leaches into the water.