Testing for food intolerance can be very simple and inexpensive to very complex and expensive. After discussing your suspicions and symptoms with your physician you may be advised to keep a food log. A food log is simple. You write down what you eat and any symptoms that you have after you eat. After a period of time of keeping the food log your physician will review it and determine which foods you are intolerant of. 

Another test that’s easy is the food elimination diet. With this diet your physician will place you on s simple diet, such as the BRAT diet. BRAT is bananas, rice, applesauce and toast. If you are suspected of being fructose intolerant your physician will not place you on a diet containing fruit. The elimination diet is followed by a challenge in which one food is added to the diet at a time to determine the source of the intolerance. Note that you can be intolerant of nuts and not have an allergy. Symptoms are usually mild and may include diarrhea and heartburn. 

Blood testing is available to people suspected of having lactose intolerance and gluten intolerance as both of these are genetically based. In this test your physician actually tests your glucose levels after you consume a beverage loaded with lactose, such as milk. In a person who is lactose intolerant, the glucose levels will not rise. This is not normal. Another test that can be performed to determine lactose intolerance is the hydrogen breath test. In this test your breath is checked after you consume a lactose rich drink. If you are lactose intolerant your breath will contain high amounts of hydrogen because your body is not breaking down the lactose you just consumed. 

Endoscopy and biopsy is used in determining whether or not you have celiac disease. This is when your body begins to consume your small intestine after you eat gluten rich foods such as wheat, rye and barley. Some people can have gluten intolerance and not have celiac disease. 

Treatment for food intolerances includes avoiding the foods you are intolerant of. If you have an infant that is lactose intolerant, you place them on soy based formula. Introduce foods to your baby one at a time and for several days to determine if there is an intolerance. If you are lactose intolerant, you drink soy milk or lactose free milk. There is even lactose free ice cream. If you have fructose intolerance you should avoid fruit, sweeteners and drinks that contain fructose. 

Learn to read labels. Avoid the foods that give you less than desirable effects. Remember, anyone can develop an intolerance to any food at any time throughout their lives. If you feel you have food intolerance, notify your physician and work with him/her to plan a course of action.