A food intolerance and a food allergy are two different things, but symptoms are often the same, so people frequently don’t understand the difference. I usually tell people my kids are “allergic to several foods,” just because I don’t feel like explaining what multiple protein intolerance is.
In a nutshell, food allergies cause an immune response that can be found with allergy testing. They often illicit an immediate reaction (hives, nausea, cramping, rashes) and sometimes a life-threatening response (anaphylaxis).
Food intolerance symptoms are generally in the gastrointestinal system (i.e. diarrhea, cramping, bloating, acid reflux), and don’t generally involve an immune-system attack (there is debate as to whether food intolerances show up on a tests). One way to discover if you, or your baby have a food intolerance is to go on an elimination diet.
Celiac disease is an autoimmune disease similar to a true-food allergy because it causes an immune response. Symptoms are most often gastrointestinal, but a range of other symptoms are common. Celiac sufferers are not at risk of anaphylaxis like food-allergy sufferers. Celiac sufferers must avoid gluten, the protein found in wheat, barley and rye. Sufferers should also avoid oats, unless they are certified gluten-free because oats are grown and transported with wheat, and thus are often contaminated with gluten.