Stevia, a natural sweetener that serves as a non-calorie alternative to sugar, comes from the Stevia rebaudiana plant, which is native to Paraguay. Overuse of some alternate sweeteners might cause loose bowels and diarrhea in some, but that effect is not evident when using refined stevia. The FDA, however, has defined only the refined form of stevia as safe, not whole leaf stevia. As such, use of the stevia herb might have additional side effects. Talk to your doctor before adding any herb to your diet.
Stevia: The Herb and the Sweetener
Before manufactures refined the stevia leaf for use as a sweetener, it was a food staple for native Indians in Paraguay. Now cleared for use as a food additive, stevia is a popular sugar substitute for those counting calories and trying to lose weight. Highly refined extract of stevia might cause mild nausea or a feeling of being full, according to Memorial Sloan-Kettering Cancer Center, but diarrhea is not listed among the side effects.
In 2009, the U.S. Food and Drug Administration approved the use of refined stevia as a food additive. At that time, the FDA stated that it found “no basis to object to the use of certain refined Stevia preparations in food.” However, only certain highly-refined stevia products are approved for use. Whole-leaf stevia and crude stevia extracts are not approved as a food additive, according to the FDA website.
Sweeteners and Diarrhea
Since so many artificial sweeteners are on the market, it can be confusing as to which ones have the most potential of triggering diarrhea. The International Foundation for Functional Gastrointestinal Disorders lists fructose, lactose, sorbitol and manitol as potential diarrhea triggers, but does not include stevia in that list.
The FDA does not regulate the sale of stevia in leaf form and it is available in health food stores in bulk or as an ingredient in other herbal products. “Leung’s Encyclopedia of Common Natural Ingredients” lists stevia leaf as having a weak hypoglycemic activity, so those who suffer from blood sugar disorders should not use stevia leaf unless directed to so by a doctor. See your doctor if diarrhea persists or if you have additional symptoms.