Some people can become either acutely ill or suffer a variety of seemingly unrelated symptoms caused by certain foods they are eating. A food intolerance is your body’s way of saying that this food is not right for your body. The incidence of food intolerances has increased five times over the past two decades. Food intolerances can cause symptoms ranging from nausea, bloating, abdominal pain, and diarrhea to joint pain, asthma, skin rashes, and fatigue. You may have a food intolerance and not realize it.