Oh Boy, More Soda News: Could Its Brown Coloring Cause Cancer?

So this has been a big week for bubbly beverages, huh? First, the news that diet soda might be linked with strokes and now this:

The Center for Science in the Public Interest says that the stuff that gives the soda its brownness--the "caramel coloring"--might possibly be carcinogenic,. The group is petitioning the FDA to ban the coloring or at least put warning labels on the cans, saying that 2-methylimidazole and 4-methylimidazole--two chemicals produced during the processing of soda--have been linked with lung, liver and thyroid cancer in lab mice.

There's still a lot of question marks--the FDA is reviewing the claims, and groups such as the American Beverage Association say there's no evidence the chemicals are cancer-causing to humans. A biochemist at Vanderbilt University, Fred Gurengerich, says: "My advice would be just to relax ... I did some simple math. ... If you look at the study in terms of what the mice got, in terms of causing any effect, a human being would have to drink more than 1,000 sodas a day."

When you look at food labels, are there any ingredients that you actively try to avoid?