Many people are unable to tolerate one or more common, everyday foods. Food allergies and food sensitivities differ, but both may create bothersome symptoms which overlap. If you have had undiagnosed digestive issues, skin rashes, congestion, or multiple bouts of what you believe to be food poisoning, your diet may be the culprit.
A true food allergy directly involves the immune system. When you have a food allergy, your body incorrectly identifies a harmless food protein as a danger. This triggers immune cells to release inflammatory chemicals such as histamine. Symptoms typically appear soon after eating. They can include hives, swelling of the mouth, nausea, stomach pain, and in severe cases, anaphylaxis. Many food allergies are diagnosed in childhood; however, adult onset allergies are becoming increasingly common. These may develop even with foods that were previously well tolerated, resulting in symptoms being inaccurately attributed to food poisoning or a virus.
Food sensitivities are related to the immune system, but not in the same way as a traditional allergy. The digestive system is designed to tolerate non-harmful foods. When the body is having difficulty breaking down certain foods, or if the gut lining is not functioning properly, that tolerance can be reduced. This results in a release of non-allergy immune system proteins slowly over time which can lead to bloating, IBS, constipation, diarrhea, weight gain, migraines, fatigue, and skin rashes. Because these issues develop slowly, it is often difficult to pinpoint food sensitivities as the cause.
If you or your provider suspect that your diet is causing your symptoms, the first step is to perform diagnostic testing and consider food eliminations. If those symptoms include breathing issues and/or throat swelling, you should meet with an allergist. For lesser concerning symptoms, your doctor can order both IgE (allergy) and IgG (sensitivity) blood tests which may help you to identify your triggers.
Eliminating dietary triggers for your symptoms often provides significant relief. How long you eliminate a food, and if/when you should reintroduce it depends on the type of reaction and your personal health and lifestyle goals. You may be prescribed some supplements or medications to help your body heal during this process.