Apparently, FDA approval can wait. This week, the Coca-Cola company will begin selling a diet drink sweetened with the somewhat controversial herbal supplement stevia. For three diet flavors of its Odwalla juices, Coke will use the Truvia brand of sweetener, which it developed in partnership with Cargill earlier this year.

Unlike most of the products derived from the stevia herb, Truvia isn't labeled as a "dietary supplement," but it has yet to be approved by the FDA. Coke is moving forward with Truvia-sweetened products anyway, though PepsiCo is still holding off. For the details, read more.

Both Coke and Pepsi expect the FDA to rule that stevia is "generally regarded as safe," but Pepsi plans to wait for official approval. Each beverage giant has its own brand of stevia: Coke's Truvia will face off against Pepsi's PureVia brand, which it plans to use in SoBe Life Water and a new juice called Trop 50. You can already buy one brand of soda made with stevia, called Zevia. But safety concerns persist:

As recently as August 2007, the FDA has questioned the safety of stevia.

"In fact, literature reports have raised safety concerns about the use of stevia, including concerns about control of blood sugar, and effects on the reproductive, cardiovascular and renal systems," the FDA wrote in a letter to Hain Celestial about its Zingers To Go Tangerine Orange Wave Herb Tea. The tea's ingredients included stevia.

But manufacturers have become more confident that the FDA won't oppose their use of stevia sweeteners, with trade publication Beverage Digest having even predicted that the sweetener would be approved last month.

Will you try the new Odwalla drinks before — or even after — the FDA's approval comes through?