This may be caused from the prebiotic inulin. If prebiotics are not a part of your regular diet, you may experience some indigestion when first consuming Collagen Bars and Bites. This is a temporary side effect from feeding your gut flora and should go away as your body adjusts. Inulin is an ingestible long-chain soluble fiber that your gut flora (the good bacteria you already have in your gut) can consume and ferment. You can think of prebiotic foods as high quality fuel for your gut bacteria.