You might be someone who needs to ease into the Zone a bit more slowly. Yes, some people have a hard time adjusting to the sudden change. Start out more slowly. Eat veggies cooked at first, they will digest more easily. Go easy on the gas-forming foods, like beans, onions, cauliflower, broccoli, especially in their raw state. If it a gas problem, I have heard that Bean-o works pretty well for that (I have never tried it).