Soda and Cancer: Is There a Link? 37706

A new study by Consumer Reports reveals concerning levels of a potentially carcinogenic chemical—4-methylimidazole (4-MEI)—in soft drinks. In the study, researchers looked at levels of the chemical, formed during the production of some types of caramel color (an artificial coloring commonly found in foods and drinks) in 81 cans and bottles of popular soft drinks purchased in California and New York between April and September 2013. In December 2013, 29 new samples of brands that initially tested above 29 micrograms of 4-MEI were purchased from the same areas and retested.

Both rounds of testing found 4-MEI levels in Pepsi One and Malta Goya samples exceeded 29 micrograms per can or bottle. In the initial round of testing, some of the other brands purchased in California had average levels around or below 29 micrograms per can, although New York samples of those same brands tested much higher. In the second round of testing, the levels in the New York samples had come down. As stated in a Consumer Reports article, "...regular Pepsi from the New York area averaged 174 micrograms in the first test and 32 micrograms in the second." The article also says that the drop in amounts of 4-MEI from the first round of testing to the second suggests that some manufacturers may have taken steps to reduce levels in their products.

The Consumer Reports analysis also found that the products purchased in California didn't have a cancer-risk warning label. That's surprising since as of January 7, 2012, manufacturers have been required to put such a warning on the label of a product sold in the state if it exposes consumers to more than 29 micrograms of 4-MEI per day.

According to a 2007 report by the National Toxicology Program (NTP), a 2-year mouse study showed an increased incidence of certain lung tumors caused by consuming levels of 4-MeI that far exceed current estimates of human exposure. And in a 2010 report by the International Agency for Research on Cancer (IARC), 4-MEI was deemed as "possibly carcinogenic to humans."

In its assessments in 2011 and 2012 of 4-MEI in caramel colors, the European Food Safety Authority (EFSA) concluded that they have no concerns about Europeans being exposed to 4-MEI from the use of caramel coloring in food.

According to an NBC News article, while the U.S. Food and Drug Administration (FDA) says there's no evidence 4-MEI is unsafe, an FDA spokesperson said the agency will take a closer look after Consumer Reports complaints. Currently, there are no federal limits for 4-MEI levels in foods and beverages.

We all know soda is a popular beverage among children and adults alike. We also know that for many reasons, kids (and all of us) should drink less—if any—soda. Besides being a source of empty calories (mostly from sugar), soda has been linked with everything from obesity to aggressive behavior in children. The fact that caramel color found in soda may promote cancer adds even more incentive for kids to sip less soda and more water and other nutritious beverages. I also agree with the Center for Science in the Public Interest statement that says, in an article about 4-MEI, that "soda drinkers should be much more concerned about the high-fructose corn syrup or other sugars used in soft drinks" and that "soda drinkers are much more likely than non-soda drinkers to develop weight gain, obesity, diabetes, and other health problems."

If we want to limit our family's exposure to the potentially cancer-causing 4-MEI, we need to look beyond soda since other foods and beverages are sources. According to the FDA, the chemical can form as a byproduct in some foods and beverages when cooked—for example, when coffee beans are roasted and when meats are roasted or grilled. According to the Office of Environmental Health Hazard Assessment (OEHHA), other potential sources of 4-MEI include include beer, soy sauces, breads and other products can also be sources.

Until we know more, a great way to protect kids—and ourselves—from overexposure to potentially harmful ingredients like 4-MEI is to read ingredients lists on food labels. Not all potentially harmful ingredients will be listed, and at times you'll need a figurative magnifying glass. For example, although you won't see 4-MEI listed on an ingredients list, you will see caramel color—and some caramel color will contain 4-MEI. We can also use safer cooking methods when preparing foods including meats. For example, when cooking meats, we can limit the creation of potential cancer-causing chemicals by using smaller pieces, trimming visible fat, using certain herbs and/or marinades, precooking meat in a microwave and cooking it at a lower temperature or for less time. We can also mix up the foods and beverages we feed our kids week to week to maximize nutrient intake and minimize exposure to substances that can potentially cause harm.

For more on food additives, check out CSPI's Chemical Cuisine here.

Image of little girl drinking a soft drink via shutterstock.