Also consider that you may have alergies( food sensitivities ). If you don't know it might be best to rotate your diet. I notice some body builders have a daily routine(like eating eggs daily or the same protien powder every day) and that could be tricky for some people. Some of the most common alergens are dairy,soy, wheat (gluten),nuts, corn, eggs and shellfish. You can try rice protien or pea protien, generaly tolerated by most. Those might work for you. Be healthy.