Unpleasant reactions to food, including diarrhea and flushing, can be due to number of causes. Some people who think they have a food allergy actually have a food intolerance, which can cause many of the same symptoms but generally is not as dangerous as an actual allergy. A doctor can verify the cause of your food-related symptoms.
Allergies
The foods that are most likely to cause allergic reactions include eggs, milk, peanuts, soy, shellfish, tree nuts and wheat. In an allergic reaction to a food, your body mistakenly believes the food is dangerous and activates your immune system to fight the food. Symptoms include rash, swelling, runny nose, abdominal pain, tingling mouth, diarrhea, cramps, coughing and wheezing. Severe allergic reactions may cause anaphylaxis -- a serious reaction the includes your throat swelling so you can't breathe -- itching, facial flushing and shock. Anaphylaxis needs to be treated immediately with a shot of epinephrine.
Food Intolerances
Food intolerances don't involve an immune response and, although unpleasant, usually are not dangerous. They usually are caused by difficulty digesting foods or components in those foods. Common food intolerances include lactose intolerance, gluten intolerance, a sensitivity to food additives and histamine intolerance. Symptoms of a food intolerance may include flushing, diarrhea, headaches, indigestion and burping.
Diarrhea
Diarrhea involves having very loose or runny stools at least three times per day. If you have diarrhea, you need to keep hydrated because this condition increases your risk for dehydration. Diarrhea is more common with food intolerance -- especially lactose intolerance or an intolerance to sugar substitutes -- than with food allergies, although it does occur in some cases of food allergies. Diarrhea usually will resolve itself within one to two days, so speak with your doctor if it persists longer than this, as it could be a sign of a more serious problem.
Flushing
If you experience flushing, your face will become warm and turn red. This reaction may occur if you have a food allergy and go into anaphylaxis. It also is a common symptom of food intolerances, including those to sulphites, nitrites and nitrates, MSG and histamines. However, some people also become flushed after consuming alcohol, hot beverages or spicy foods even if they do not suffer from food allergies or intolerances.
Treatment
The best way to treat either food allergies or food intolerances is to avoid foods that cause you problems. Antihistamines might help treat some of the symptoms that occur with minor allergic reactions and food intolerances. People with severe allergies might need to carry an epinephrine autoinjector to treat anaphylaxis in case they accidentally consume the food they are allergic to. If you need to use an epinephrine autoinjector, go to the emergency room afterward, as you could need additional treatment.
References
- Nemours KidsHealth: Food Allergies
- MayoClinic.com: Milk Allergy: Symptoms
- University of Maryland Medical Center: Food Allergy or Food Intolerance?
- American Journal of Clinical Nutrition: Histamine and Histamine Intolerance
- New Zealand Dermatological Society Incorporation: Flushing
- National Digestive Diseases Information Clearinghouse: Diarrhea
