Food sensitivities and intolerances

Food sensitivities

A food sensitivity is an adverse reaction to a food that other people can safely eat. Food sensitivities include food allergies, food intolerances and chemical sensitivities.

Food allergies

Food allergies are triggered when a person's immune system mistakes a food protein for something harmful. The first time the body is exposed to such a protein, it responds by creating antibodies called immunoglobulin E (IgE). The next time there is exposure to this same food protein, the body releases IgE antibodies and chemicals like histamine. Histamine is a powerful chemical that causes a reaction in the respiratory system, gastrointestinal tract, skin and/or cardiovascular system, and in the most extreme cases can be fatal.

Fast facts

Food allergies affect as many as six percent of young children and three to four percent of adults.

Chemical sensitivities

These occur when a person has an adverse reaction to chemicals that occur naturally in, or are added to, foods. Typically people may react to caffeine in coffee, tyramine in aged cheese, and the flavour enhancer monosodium glutamate, also known as MSG.

Food intolerances

A food intolerance is a food sensitivity (such as lactose intolerance) that does not involve the immune system. Unlike food allergies or chemical sensitivities, where a very small amount of food can cause a reaction, it generally takes a 'normal'-sized portion to produce the symptoms of food intolerance. Reactions are likely to originate in the gastrointestinal system and are usually caused by an inability to digest or absorb certain foods, or components of those foods.

Fast facts

Celiac disease is an inherited intolerance to gluten.

What should you do?

If your child experiences an adverse reaction to a food, consult your family doctor to determine if the cause is a food allergy, intolerance or sensitivity.

Report a problem or mistake on this page
Please select all that apply:

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: