Understanding Food Allergies and Intolerances

Allergies are immune system reactions caused by foods. While they can be serious or life-threatening, some individuals may also experience less serious symptoms like rashes and bloating.

Food intolerances are physical reactions to certain foods that do not involve the immune system. They may be caused by an enzyme deficiency or sensitivity to food additives.

Symptoms

If you experience stomach discomfort, bloating or diarrhoea after eating certain foods, your doctor may suspect a food allergy or intolerance. Reactions can range in intensity from mild to severe and affect many parts of the body.

People with food allergies react to an allergen, which is a specific protein present in food. Once this protein enters your digestive tract, your immune system releases immunoglobulin E (IgE) antibodies in an effort to attack it.

This can cause a series of unpleasant reactions in your body, such as itchy or watery eyes, hives, asthma, difficulty breathing and stomach pains. In extreme cases the reaction can be so severe it could prove life threatening; anaphylaxis.

Food intolerance symptoms may appear immediately after eating a food, but they may take hours or days to manifest and are difficult to pinpoint. Fortunately, most food intolerances resolve when you remove the offending item from your diet. You can gradually reintroduce that same food after some period of abstinence depending on how long your tolerance has been established for it.

Diagnosis

Allergies are caused by your immune system’s reaction to certain foods. If the allergy is severe, it could prove lethal.

Food intolerances can also be caused by your body’s digestive system reacting to certain foods. Lactose intolerance, for example, occurs when milk sugar does not break down properly in your system.

Your doctor may ask you to keep a journal of when and what you eat in order to diagnose your condition. They then refer you to an expert for further testing.

Allergy testing typically entails either skin pricking or blood tests to measure the presence of allergy-specific IgE antibodies in your body. While these procedures are more costly and take longer to complete, they can confirm a positive diagnosis.

Treatment

Food allergies and intolerances both cause symptoms that can be life-threatening if left untreated. In extreme cases, those with a food allergy may experience anaphylactic reaction (anaphylaxis), necessitating emergency treatment with an epinephrine injection to reverse the reaction.

Contrary to a food intolerance, which involves an immune response, food intolerances are generally caused by a deficiency of digestive enzymes and may manifest symptoms such as gas, bloating, abdominal pain, diarrhea or irritability.

A doctor or allergist can diagnose whether you have a food allergy or intolerance. They will likely ask you to keep a food journal, which records all meals eaten and any symptoms experienced afterward.

Prevention

Food allergies and intolerances are incredibly common, affecting people from around the globe. While there is no one-size-fits-all solution for them, symptoms can be managed by avoiding foods that trigger an allergic reaction or taking supplements to help your body digest what you eat.

Be mindful when dining out, as many restaurant dishes can contain allergy-triggering foods you might not expect. For instance, eggs may be included in salad dressings and peanuts may be an ingredient in certain sauces.

If you suspect you might have a food allergy, your doctor can perform skin testing to measure how much of an allergen your immune system reacts to when exposed. Blood tests such as RAST or ELISA can also confirm the diagnosis.