I was aware of the fact that aspartame consumption was thought to be a factor in obesity, but according to Dr. Mark Hyman (Ultra-Metabolism) Stevia and xylitol do the same thing.
"There’s no doubt about it. Artificial sweeteners cause obesity.
"Avoid artificial sweeteners, including aspartame, acesulfame, sucralose, sugar alcohols such as malitol and xylitol (pretty much anything that ends in “ol”), as well as natural artificial sweeteners like stevia.
"Stop confusing your body. If you have a desire for something sweet, have a little sugar, but stay away from “fake” foods.
"Eating a whole-foods diet that has a low glycemic load and is rich in phytonutrients and indulging in a few real sweet treats once in a while is a better alternative than tricking your body with artificial sweeteners -- which leads to wide scale metabolic rebellion and obesity."