What’s the difference between a food intolerance and a food allergy?
Answers from James T C Li, M.D., Ph.D.
A true food allergy causes an immune system reaction that affects nume- rous 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 often limited to digestive problems.
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 prevent a reaction. For example, if you have lactose intolerance, you may be able to drink lactose-free milk or take lactase enzyme pills (Lactaid) to aid digestion.
Causes of food intolerance include:
Absence of an enzyme needed to fully digest a food. Lactose intole- rance is a common example.
Irritable bowel syndrome. This chronic condition can cause cramping, constipation, and diarrhea.
Celiac disease. Celiac disease has some features of a true food allergy because it involves the immune system. However, symptoms are mostly gastrointestinal, and people with celiac disease are not at risk of anaphylaxis. This chronic digestive condition is triggered by eating gluten, a protein found in wheat, including khorasanand, rye, barley, oats, and other grains.
If you have a food allergy, you may be at risk of a life-threatening 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. You may need to carry an emergency epinephrine shot (Adrenaclick, Auvi-Q, EpiPen) for emergency self-treatment.
From Antonella Cianferoni, MD, PhD and Antonella Muraro, MD, PhD
Although a wide range of foods has been reported as the cause of anaphy- laxis, the most commonly implicated foods worldwide are Nuts; namely almonds, hazelnuts, walnuts, cashews, pecan nuts, Brazil nuts, pistachio nuts, macadamia (or Queensland); Peanuts; Soybeans; Milk (including lactose); Egg, Sesame seeds, Fish, and shellfish, in both adults and chil- dren.
Other less common are Crustaceans (for example prawns, crabs, lobster, crayfish); Celery (including celeriac); Coconut; Mustard; Sulphur dioxide /sulphites, where added and at a level above 10mg/kg or 10mg/L in the finished product. This can be used as a preservative in dried fruit; Lupin, which includes lupin seeds and flour and can be found in types of bread, pastries, and pasta; and Molluscs like, mussels, whelks, oysters, snails, and squid.
However, the individual food allergy varies by culture and population. For example, peanut allergy is one of the most common causes of anaphylaxis in the United States, United Kingdom, and Australia, but is rare in Italy and Spain (where consumption of peanut is significantly lower than in the United States) or China (where peanut consumption is similar to that in the United States).