Obesogens—a term coined by Bruce Blumberg, a biology professor at the University of California, Irvine in 2006—are dietary, pharmaceutical, or industrial compounds that alter metabolic processes and predispose some people to gain weight. Simply put, obesogens are toxins that make us fat. The idea that environmental toxins could be making us fat was only introduced in 2002, so it’s a recent idea. And it’s catching on.

In fact, the role of environmental chemicals in obesity was recently acknowledged by the Presidential Task Force on Childhood Obesity and the National Institutes of Health (NIH) Strategic Plan for Obesity Research. The NIH is currently funding research that investigates the role of environmental toxin exposure in obesity, type 2 diabetes, and metabolic syndrome.

The list of potential obesogens is growing. “There are between fifteen and twenty chemicals that have been shown to cause weight gain, mostly from developmental exposure,” according to Jerry Heindel from the National Institute of Environmental Health Sciences, quoted in a report published in the journal Environmental Health Perspectives. Most obesogens are endocrine disruptors—that is, they interfere with normal hormone function. Many endocrine disruptors are commonly encountered in everyday products. Chemical pesticides, phthalate plasticizers, bisphenol A (BPA), and fire retardants are ubiquitous in our homes and in our bodies.

If most of us (probably all of us) are exposed to these obesogens, why doesn’t everyone get fat? Well, first of all, most of us are getting fat. Over two-thirds of Americans are overweight or obese. Blumberg addresses the other one-third, “I would not want to say that obesogen exposure takes away free will or dooms you to be fat. However, it will change your metabolic set points for gaining weight. If you have more fat cells and propensity to make more fat cells, and if you eat the typical high-carbohydrate, high-fat diet we eat, you probably will get fat.”

Blumberg recommends reducing exposure to endocrine disrupting chemicals, stating, “Eat organic, filter water, minimize plastic in your life.” Here, here! I hope the research that comes out of the NIH grants will move us toward some meaningful change.