The natural sweetener erythritol does not appear to carry the adverse effects associated with other low and non-caloric natural and artificial sweeteners and may actually have antioxidant potential. For a while it was only available in Japan but now it's becoming more accessible. It's found naturally in pears and grapes, but industrially we have yeast make it for us. It doesn't cause cavities and hasn't been implicated in some of the disorders tied to other sweeteners such as fibromyalgia (see my video Aspartame-Induced Fibromyalgia), preterm birth (Diet Soda and Preterm Birth), headaches, hypertension, brain disorders, and platelet disorders (see A Harmless Artificial Sweetener).
What about stevia? The jury is finally in. The reason it's been such a long time coming is that research out of Japan in the '90s found that steviosides, the active ingredient in stevia, appeared totally harmless, but in the guts of rats intestinal bacteria transformed steviosides into something called steviol, which is toxic, causing a big spike in mutagenic DNA damage (see the graph in Is Stevia Good For You?). So the question was do we have those same rat bacteria in our guts, and it turns out we do. So we now know that when we eat stevia, mutagenic compounds are produced in our colons and absorbed into our bloodstream. The only remaining question was how much.
In the World Health Organization's evaluation of food additives, they consider up to 4 mg/kg of body weight safe. So that's 1.8 mg per pound. If you multiply your ideal weight in pounds by 1.8, that's about how many milligrams of stevia compounds you should stay under on an average daily basis. As long as one consumes less than, say, two stevia-sweetened beverages a day, stevia can be considered harmless. Erythritol may be even better than harmless, though, as you can see in my 2-min. video Erythritol May Be a Sweet Antioxidant.
There are two caloric sweeteners that are health-promoting--can you guess which ones? Check out The Healthiest Sweetener for a comparison of agave nectar, blackstrap molasses, brown rice syrup, corn syrup, brown sugar, date sugar, honey, maple syrup, raw cane sugar, and turbinado sugar.
-Michael Greger, M.D.
Image credit: Lisa Brewster / Flickr