Can chemicals that are added to breakfast cereals and other everyday products make you obese? Growing evidence from animal experiments suggests the answer may be "yes." But confirming these findings in humans has faced formidable obstacles until now.

A new study published in Nature Communications details how Cedars-Sinai investigators developed a novel platform and protocol for testing the effects of chemicals known as endocrine disruptors on humans.

The three chemicals tested in this study are abundant in modern life. Butylhydroxytoluene (BHT) is an antioxidant commonly added to breakfast cereals and other foods to protect nutrients and keep fats from turning rancid; perfluorooctanoic acid (PFOA) is a polymer found in some cookware, carpeting and other products; and tributyltin (TBT) is a compound in paints that can make its way into water and accumulate in seafood.

The investigators used hormone-producing tissues grown from human stem cells to demonstrate how chronic exposure to these chemicals can interfere with signals sent from the digestive system to the brain that let people know when they are "full" during meals. When this signaling system breaks down, people often may continue eating, causing them to gain weight.

Each of these chemicals damaged hormones that communicate between the gut and the brain. Other scientists have shown these compounds can disrupt hormone systems in laboratory animals, the new study is the first to use human pluripotent stem cells and tissues to document how the compounds may disrupt hormones that are critical to gut-to-brain signaling and preventing obesity in people.