It can be hard to figure out just which sugar alternative is the best choice, especially if you're trying to limit yourself to more-natural alternatives. Both organic stevia-based products and erythritol have their benefits, but they should only be consumed in limited amounts to limit the risk of side effects.
Stevia-based sugar substitutes are made with a substance found in the stevia plant called rebaudioside A, which is approximately 200 times sweeter than sugar. Reb A can't be absorbed by your body, so it doesn't have any calories or affect your blood sugar levels, but some stevia-based sugar substitutes contain other ingredients that might contribute a small number of calories per serving.
Erythritol is a sugar alcohol that's 60 to 80 percent as sweet as sugar, but it isn't completely digested so it has a very limited effect on blood sugar levels. Five grams of erythritol have just 1 calorie.
Some stevia-based sweeteners also contain erythritol. This can help sweeten the products further while limiting the potential bitter aftertaste that people experience when consuming stevia, and it also adds bulk to stevia products to make them easier to measure.
Potential Side Effects
Although stevia doesn't usually have any side effects, it can cause nausea and feelings of stomach fullness. Erythritol can have a laxative effect at high doses, as is the case with other sugar alcohols.
Pregnant or nursing women shouldn't use stevia at all. High doses of stevia may have weak mutagenic activity, according to the Memorial Sloan Kettering Cancer Center. Whole stevia leaves were also traditionally used as a contraceptive by the Guarani Indians in Paraguay. Those on blood pressure or diabetes medications should check with their doctor before using stevia-based products, as they may interact with these medications. People allergic to ragweed may be allergic to stevia as well.
Only products made with rebaudioside A, not whole-leaf stevia or other stevia extracts, are approved by the U.S. Food and Drug Administration for use in food. The World Health Organization recommends a limit of no more than 1.8 milligrams of stevia per pound per day, which means no more than two or three packets containing about 100 milligrams of stevia if you weigh about 150 pounds. The organization didn't set a limit for erythritol because of the relatively limited risks associated with its use.