A consumer advocacy group says chemicals that give cola its distinctive caramel color may cause cancer.
CBS News Medical Correspondent Dr. Jennifer Ashton explained on "The Early Show" that the Center for Science in Public Interest (CSPI) is concerned about a chemical that is liberated during the production process of making colas.
"They say (the chemical) has been found in government studies to cause cancer in animals. The State of California is so concerned about this that they have listed one of these ingredients on their list of substances known to cause cancer, and they want to limit the amount to no more than 16 micrograms a day," she said. "To put that into context for you, 20 ounces of cola can contain 12 times that amount."
The artificial brown coloring, according to the CSPI, is made by reacting sugars with ammonia and sulfites under high pressure and temperatures, and those reactions "result in the formation of 2-methylimidazole and 4 methylimidazole, which in government-conducted studies caused lung, liver, or thyroid cancer or leukemia in laboratory mice or rats."
Co-anchor Chris Wragge said, "Over half of the population drinks soda. I mean this is really -- you've got to really scale this back."
Ashton said, "Absolutely. Now, there's two sides to every story here, Chris. And even this watchdog group themselves say the risk is small. The (American) Beverage Association is outraged. They say this is not based on science. This has only been found to cause possibly cancer in animals -- not in humans -- that these substances are found everywhere. And much more research needs to be done. And the FDA (Food and Drug Administration) is looking into it."
Ashton added that many condiments and drinks have the light brown coloring found in colas.
She said, "When you heat sugar it makes a light brown coloring. ... This is just the natural caramel coloring. When you look at darker food products, this is the color you get; this is a cosmetic result. This is not adding to the flavor in any way, and it is not just found in cola. It's found in steak sauce, soy sauce, some maple syrups, some dark beer."
As far as overall health, Ashton said, "Our bodies are about 60 percent water -- not 60 percent soda. So once in awhile, in moderation, probably the risk is going to be low. Again, not everything that's found to be dangerous in a lab rat or animal is going to be really dangerous to a human being. But we need to understand that you can get 100 percent of your beverage needs just by drinking water. And then you're doing away with the chemicals, you're doing away with the sugar, the sweets and all of those things. It's an individual decision, but medically, really, your body just needs water."
Wragge asked, with theconcerning sodas, would Ashton stop drinking it.
"Probably not," she said. "I'd probably continue to drink my soda. But you need to understand the risks."