IDK, maybe for some people that have adverse reactions to artificial sweeteners it can exhibit in ways you say. But I dont think that all people with fibro or IBS or CFS got it from sweeteners. I have fibro, and while i get some artificial sweetener from my pop, i go for days with none and do not feel better, gone for weeks really and felt the same. I personally blame my fibro on either a very stressful childhood, or possibly from being double vaccinated as a child. But I dont think it is sweeteners.