Skip to main content

Study: Food Coloring Health Risk

If your favorite soft drink is brown, you might want to take caution. According to an analysis conducted by Consumer Reports, some sodas may contain high levels of a coloring additive known to cause cancer in mice.

In the 2014 study, researchers with Consumer Reports bought 12 popular brands of bottled and canned sodas to test for 4-methylimidazole, also called 4-MEI. You know it as caramel food coloring—the chemical that makes many foods and beverages golden-brown. It’s one of the most commonly used food coloring in the world.

While there is no medical consensus that 4-MEI causes humans harm, the World Health Organization and the state of California believe it could cause cancer when consumed in high doses based on experiments performed on mice.

California now requires manufacturers to label products with a cancer warning if ingestion exposes people to more than 29 micrograms of 4-MEI. In the Consumer Reports analysis, Pepsi, Diet Pepsi, Pepsi One and Malta Goya all were found to have 4-MEI levels above that threshold in three or more of its four test groups.

Coca-Cola, Diet Coke and Coke Zero, as well as Dr. Pepper and A&W Root Beer contained amounts of 4-MEI below the 29-microgram level when Consumer Reports tested them. The clear soft drink Sprite contained "no significant level" of the coloring, the report said.

The Food and Drug Administration does not believe there are any immediate or short-term health risks in food that contain low levels of 4-MEI.


Limit Soda Intake

This fact doesn't give you carte blanche to guzzle as many soft drinks as you want, though. Julie Metos, PhD, RD, an assistant professor and associate chair of the Department of Nutrition and Integrative Physiology at University of Utah Health, says there are plenty of other reasons to enjoy this treat in moderation.

"Generally speaking, soda is one of the biggest contributors to excessive sugar in the American diet," Metos says. A 12-ounce can has about 150 calories that scientists think are going straight to our hips, bellies, and backsides.

"Looking longitudinally at the weight gain in the U.S., they can actually show that the weight gain is likely from that extra soda that we've been consuming over the last 20 years," Metos says. "There's evidence that it's one of the major contributors to overweight and obesity."

Metos explains that since they're in liquid form, the sweeteners in soft drinks don't make you feel as full as eating solid food, which can make soft-drink lovers overeat. "The sugar is very lipogenic, so it contributes to fat stores and changes your metabolism in a way that's detrimental to your health," she adds.

Unfortunately, sticking to diet soda doesn't get you totally off the hook either.

"I think diet soda is a better option, but it's not a perfect one," she says. According to Metos, since you're still drinking something sweet, your palate stays accustomed to sugary tastes rather than more healthful, natural flavors.