This Chemical In Your Food Makes You Look 11 Years Older

We all know there’s sketchy stuff in our food—high fructose corn syrup, trans fats, pink slime, and artificial food dyes just to name a few. And often, we can avoid the dangerous stuff by diligently reading our food labels. But it’s not always that easy.

A new study in the American Journal of Epidemiology finds that exposure to the metal cadmium via food and the environment, even at relatively low levels, can significantly shorten our telomeres—the protective caps of DNA on the ends of chromosomes that are associated with aging. Shorter telomeres can up your risk for cardiovascular disease, diabetes, cancer, and other age-related ailments.

Unfortunately, cadmium doesn’t appear on food labels because, well, no one knows it’s there in the first place. “We have limits for how much cadmium can be in the water and in the air, but not food,” says lead study author Ami Zota, assistant professor of environmental and occupational health at Milken Institute School of Public Health. The FDA does not test for cadmium or require manufacturers to, so only those companies that do test—very few—are  actually aware of what’s in products. In fact, earlier this year, independent testing by ConsumerLab found that many commercially available cocoa powders were contaminated, suggesting that there may be a need for enforced cadmium limits.

In this study, Zota and colleagues measured cadmium levels and telomere length from blood and urine samples of 6,700 individuals. People with the highest levels of cadmium, which were still pretty low, had cells that looked on average 11 years older than their actual age. But even more disconcerting was that lower levels of cadmium were associated with some degree of telomere shortening, too. In other words, “we found no threshold below which cadmium was safe,” says Zota. 

For the general population not exposed in industrial settings, the biggest sources of cadmium are cigarette smoke and food, says Zota. That’s because some plants, including tobacco, cereal grains, leafy greens, and root vegetables, can hyper absorb cadmium in the soil after they’re treated with phosphate or sewage sludge fertilizers (i.e. recycled human waste)—both known to contain the metal—or after cadmium is stirred up by mining or smelting. Of course, the cadmium content of produce will depend on where and how it was grown, which is hard to know. So instead of avoiding these nutrient rich foods, you may want to focus on eating organic when possible. According to a 2014 study, organic produce contained higher antioxidant and lower cadmium concentrations than conventional.

And there's even more you can do to stay healthy: Research suggests that getting enough iron in your diet via foods like leafy greens, pumpkin seeds, meats, and fortified cereals may decrease the amount of cadmium you absorb. And increasingly more studies show that telomeres can be lengthened by eating a diet rich in fruits, vegetables, and whole grains; exercising regularly; and reducing stress with calming yoga and meditation.