Your Oatmeal May Be Sweetened with Mercury

Study: Outdated manufacturing process taints high-fructose corn syrup, a common ingredient in processed foods.

February 20, 2009

Toxic metal, aisle 3: Many packaged foods may be contaminated with mercury, a new study suggests.

RODALE NEWS, EMMAUS, PA— High-fructose corn syrup (HFCS) is a ubiquitous food ingredient: It’s added to everything from soda to ketchup to oatmeal, both as a sweetener and to extend shelf life. Because it adds empty, often unnoticed calories to so much of the food we eat, the corn-based compound has been targeted by health experts as a contributor to rising obesity levels. And the environmental downside of devoting so much of our agriculture to corn for sweetening our food has been famously described in Michael Pollan’s book, The Omnivore’s Dilemma: A Natural History of Four Meals (Penguin Press, 2006). Now two reports suggest that those sweet calories may come with a toxic add-on: mercury, a heavy metal that’s especially dangerous to kids and unborn children.


THE DETAILS: In a commentary published in the journal Environmental Health, former Food and Drug Administration investigator Renee Dufault, PhD, and her coauthors, describe how she tested HFCS samples for mercury during her stint at the FDA. The samples came from three manufacturers that supply HFCS to the food industry; almost half of the samples had detectable levels of mercury. In response, the Institute for Agriculture and Trade Policy (IATP), a food watchdog group, tested 55 HFCS-containing consumer products. They claim to have found mercury in about a third of them. According to the IATP report, mercury may be contaminating some HFCS because of an “outdated” manufacturing process that not all HFCS makers have abandoned.

WHAT IT MEANS: These are small studies, only one of which was published in a peer-reviewed scientific journal. But they raise some disturbing questions—like, how much mercury is actually ending up in our food? Dufault estimates that in a worst-case scenario, the mercury levels found in her testing could translate to about 28.4 micrograms of mercury per day for the average American consumer. As a comparison, the EPA recommends that women of childbearing age and children keep their daily exposure to mercury below 0.1 microgram per kilogram of body weight—that’s about 5.5 micrograms per day for an average-size woman. (That recommendation is for one specific type of mercury; it’s not known which form of mercury was detected in these studies.) The study authors call for more research, and for tighter regulation of HFCS production.

While researchers and policy makers argue about how dangerous this common food ingredient may be, here are some prudent steps you can take to protect yourself:

• Avoid foods containing HFCS if you’re pregnant or elderly, and keep it out of your kids’ diet. The stuff is so omnipresent, it’s challenging to cut it out of your diet entirely, but check food labels and cut out what you can. However the mercury-tainted HFCS issue shakes out, by avoiding the sweetener you’ll dodge some unneeded calories. “I would recommend that pregnant women abstain from foods containing HFCS until we know more,” says Dufault. “Sensitive populations—newborns, pregnant women, elderly people, babies who are breast-feeding, children with Autistic Spectrum Disorder (ASD), and, possibly, healthy children— are at risk of adverse effects from long-term, chronic exposure to total mercury in food.” Mercury can impair the development of a child’s brain, affecting learning ability and IQ. The elderly are also vulnerable to its effects. Most healthy adults are probably able to handle the mercury that might be in HCFS-sweetened products, Dufault says.

• Contact the food makers. They want to keep your business, so write, e-mail, or call the makers of your favorite processed foods and demand they investigate mercury contamination in their products.

• Pressure the lawmakers. In 2007, then-senator Obama sponsored a bill that would ban the chemical process that could be causing the mercury contamination; passing that legislation would effectively eliminate this issue. To contact your congressperson: To contact your senator: To send a message to the president:

• Prepare for a sugar shock. Whether they’re sweetened by HFCS or plain ol’ cane sugar, cutting sugary processed food from your diet will lead to cravings until your body adjusts. Satisfy your sweet tooth with fresh fruit, and start the day with a full breakfast so you don’t get hit by a mid-morning sugar crash.