Guide to differences with allergy and intolerance
Food reactions are common, but most are caused by a food intolerance rather than a food allergy. A food intolerance can cause some of the same signs and symptoms as a food allergy, so people often confuse the two.
A true food allergy causes an immune system reaction that affects numerous organs in the body. It can cause a range of symptoms. In some cases, an allergic food reaction can be severe or life-threatening. In contrast, food intolerance symptoms are generally less serious and are limited to digestive problems.
If you have a food allergy, even a tiny amount of the offending food can cause an immediate, severe reaction. Digestive signs and symptoms may include nausea, vomiting, cramping and diarrhea. Other signs and symptoms can include a tingling mouth, hives, and swelling of the lips, face, tongue and throat. A life-threatening allergic reaction known as anaphylaxis can cause breathing trouble and dangerously low blood pressure. If you have a food allergy, you’ll need to avoid the offending food entirely.
Food intolerance symptoms generally come on gradually and don’t involve an immune system reaction. If you have a food intolerance, you may be able to eat small amounts of the offending food without trouble. You may also be able to take steps that help prevent a reaction. For example, if you have lactose intolerance, you may be able to drink lactose-free milk.
- If you observe a reaction after eating a particular food, see your doctor to determine whether its a food intolerance or a food allergy.
- If you have a food allergy, you may be at risk of a allergic reaction (anaphylaxis) — even if past reactions have been mild. Learn how to recognize a severe allergic reaction and know what to do if one occurs.
- If you have a food intolerance, your doctor may recommend steps to aid digestion of certain foods or to treat the underlying condition causing the reaction.