Hold up though: wasn't there a problem with stevia? The sweet leaves of the ordinary-looking plant have long been banned for food use in the USA and European Union -- and in Singapore and Hong Kong -- due to concerns over a 1985 study that suggested steviol, a breakdown product from stevioside and rebaudioside, is a mutagen in the presence of a liver extract of pre-treated rats. In other words, it could create changes in the DNA of the liver, up to and including cancer. The study, however, was widely criticized by scientists who claimed the study was conducted in a way that would also find distilled water mutagenic, and largely discarded by health food aficionados, who continued to buy stevia powder in stores where it was marketed as a "dietary supplement" thanks to a ban by the U.S. FDA.



Stevia was until very recently considered questionable by the FDA, but in December 2008 an FDA advisory prompted by Cargill's development of Truvia held that stevia with 95 percent or 97 percent rebaudioside A is safe and products containing that substance can be called foodstuffs (and not, as one soda company previously described its products, a "carbonated stevia supplement"). Truvia and PureVia are both formulated with reb A, leaving out the components of stevia leaf that provide a licorice-flavored aftertaste. It should be noted that powdered stevia is still not considered safe as a food additive; the FDA hasn't explained this distinction.

So, about that stevia-sweetened soda: there are already a few versions out there. One all-natural variety from Seattle is called Zevia (which I've tried and liked, in smallish quantities). Long-time craft soda maker Reed's, Inc. is marketing stevia-sweetened versions of its Virgil's colas, root beers, and cream sodas. But the big change is set to come from PepsiCo (PEP), who along with Whole Earth Sweetener Company (a subsidiary of the company that markets Equal) developed PureVia -- they've been making PureVia-sweetened SoBe since December 2008 -- and Coca-Cola Company (KO), which says a stevia-sweetened Sprite is on its way and has already announced a version of Odwalla sweetened with Truvia. No, I don't know why a 100 percent fruit juice needs additional sweetener, either, but I'm sure the marketers will explain it to us in due time. Given the funding behind these two new sweeteners, it seems inevitable that Nutrasweet and Sweet and Low will soon be but the cultural memory of our parents.

Truvia's television commercials and the additives branding veritably bleed the "from nature" story (a leaf dots the "i," if the green colors didn't already convince you), even though the substance is certainly highly processed and does contain other ingredients such as erythritol (a sugar alcohol derived from fruit also eagerly advertising its "natural"-ness). Many long-time proponents of stevia complain that the FDA banned the substance for decades, until food giant and deep-pocketed lobbyists Cargill, Pepsi and Coca-cola sought to use it. And health pundit Mark Sisson points us to the extremely short nature of the only study on Truvia done so far -- it was 16 weeks -- as rather too small to prove anything. Real dangers could take decades to become obvious.

Sisson goes on to make a few important points about Truvia (and, by association, PureVia): first, "it isn't 100% clear that rebiana is entirely the physiologically-acting equal of other forms of stevia used throughout the world." The way an extractive works on the body could be very different than the way the whole substance does -- take white sugar, a highly-processed substance that wreaks far more havoc on the human body than sugar cane in its whole form. Further, it's easier to overdose on a chemically-derived substance than it is on the herbal source. I agree with Sisson's second point heartily: "as it is with any artificial/altered sweetener: ask yourself if the sweetened food/drink offers any real benefit (physical or otherwise) that you couldn't get from the same or similar food/drink that's unsweetened."

Drinking four cans of Sprite a day, whether it's sweetened with pure cane sugar, high fructose corn syrup, Nutrasweet, PureVia, or some as-yet-to-be-marketed substance, is probably not entirely healthy. Truvia seems to be a positive step in the direction of whole foods: but it's a very, very small step and should not be considered a giddy slip-and-slide toward "healthy" soda. Is it terrible for you? Probably not. Is it going to improve your health? Almost certainly not. As always, moderation is the way to go.

Whether soda companies will market it this way, given the evidence so far, is unlikely.