Stress, coffee, cell phones, even pickled vegetables -- it seems like everything has the potential to give you cancer these days (here’s a short CNN post about some new candidates). Should the artificial coloring in soda be on the list? Probably not -- unless you’re drinking thousands of cans a day.
Dark sodas like Coke and Pepsi get their tint from a caramel coloring that contains a chemical called 4-methylimidazole, or 4-MI. A consumer watchdog group recently tested soda cans from several major brands and found that some had levels of 4-MI nearly five times higher than the limit set by California, and implored the FDA to require these beverages to be labeled as potentially carcinogenic.
4-MI was added to California’s list of carcinogens several years ago after a study found that mice who drank water containing massive doses of 4-MI over the course of two years had a greater risk of developing certain types of tumors.
Before swearing off soda, though, it's worth noting that a person would have to drink about 5,000 of cans of soda a day to get the equivalent dose of 4-MI that these mice were receiving. And even with these extreme doses, the story is not so simple -- the same high doses that led to increased tumors in mice actually seemed to protect against the development of other types of tumors in rats. Here are some more details about 4-MI in soda.
Too much of anything can be dangerous -- salt, sugar, and even water in high enough doses can kill you -- but that doesn’t mean to we need to avoid these things entirely. While we do know that soda can rot your teeth, lead to obesity and diabetes, and may even be associated with a higher risk for stroke, we probably don’t need to add cancer to the list of health concerns.