Allergies & food intolerances


Allergies are the body’s immune response to a substance (called an allergen) that is usually harmless. The allergic person's immune system perceives the allergen as dangerous and produces a special type of antibody (IgE) to defend itself. This starts a chain which leads to the releasing of further chemicals (including histamine) which then causes the symptoms of an allergic reaction. Symptoms vary - where most people suffer discomfort and a few people have a life-threatening reaction called anaphylaxis.

Read about the facts of water here.

Food allergies vs intolerances 

It's important to distinguish food intolerance from food allergy.
Food allergy = serious allergic reaction which can be life-threatening, onset within an hour of eating it.
Food intolerance = small amounts with no reaction, symptoms like discomfort and bloating can occur.

People can develop an allergy to almost anything. However, wheat, egg, milk, soy, peanuts and fish are the most common. 

There is usually a more delayed reaction with a food intolerance. It is also more likely to be associated with a dose-response, meaning that an individual may not react to a low dose but will react above a certain threshold level.  

Far more people have a food intolerance, unpleasant symptoms triggered by certain foods. Unlike a food allergy, a food intolerance doesn't involve the immune system.

Lactose intolerance 
Lactose intolerance is one example of a food intolerance. People with lactose intolerance lack the enzyme lactase needed to digest milk sugar (lactose) in milk and other dairy foods. This inability to break down lactose during digestion may cause diarrhea, gas, bloating and abdominal pain.
Many people believe that they are allergic to certain types of foods. The prevalence of true allergy, however, is only 1% - 4% of the South-African population, with this figure being slightly higher for children, at 3% - 5% of children having a true food allergy.

The food allergens
While food labels don't include every possible allergen, they do list the top few, which account for most food allergies:

  • Milk 
  • Eggs 
  • Peanuts 
  • Tree nuts (such as almonds, cashews, walnuts) 
  • Fish (such as bass, cod, flounder) 
  • Shellfish (such as crab, lobster, shrimp) 
  • Soy 
  • Wheat 

NOTE: A registered dietitian must be consulted to assist with a proper eating plan and personalised advice when managing any allergies. You can find a dietciian in your area on ADSA (Association for Dietetics in South Africa)

Read about Living with an Allergy or Food Intolerance.