Consumer advocates are slamming Coca Cola Co. for plans to begin selling three Odwalla drinks containing the zero-calorie sweetener stevia as early as this week, even though the U.S. Food and Drug Administration (FDA) has not yet deemed it safe, the Wall Street Journal reports. Coke rival PepsiCo, meanwhile, says it will wait for FDA okay before selling its stevia beverages Trop 50 and SoBe Life Water, according to the Associated Press.

Stevia is actually a shrub that grows in Paraquay and Brazil; an extract from it known as rebaudioside A is being touted by foodies as the "Holy Grail" of sugar subs because it's 300 times sweeter than the real thing and just as natural sans the calories. Other low or no-cal sugar alternatives such as aspartame (Equal and NutraSweet) saccharin (Sweet'N Low) and sucralose (Splenda) are artificial products.

Stevia is used in foods in a dozen countries, including Japan, according to Forbes.

The FDA is currently weighing the evidence to determine if stevia safe, but companies interested in using it are not required to await the results before marketing products containing it, according to agency spokesperson Stephanie Kwisnek.

Stevia extracts currently are available in the U.S. as  supplements that can be added to sweeten drinks and foods but the Coca Cola Corp.'s beverages would be the first  commercial products in the U.S. that contain them.

The Center for Science in the Public Interest (CSPI) urged the FDA to bar the sale of products containing stevia until more safety studies are done. The Washington, D.C.–based advocacy group cited a report conducted by toxicologists at the University of California, Los Angeles, in August indicating that stevia might cause DNA damage in rats.

"Stevia and rebaudioside A may well turn out to be entirely safe. But until more tests have been conducted and analyzed, it is reckless for food companies to begin adding it willy-nilly to the food supply and equally reckless for the FDA to stand by mutely," CSPI executive director Michael Jacobson said in a statement. "The FDA should immediately order those products off the market until all the safety testing has been done."

A Coca Cola spokesperson declined to comment on the controversy or to confirm reports that it plans to release the three drinks containing stevia this week.

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