Food allergies and intolerance

Food allergens

Overview

An allergy is an overreaction by the body’s immune system to a normally harmless substance.

Food is a common cause of allergic reactions which are becoming more common in Australia.

The allergic reaction to food is caused by a protein in the food that the immune system mistakenly believes is harmful.

A food intolerance is easily confused with a food allergy, but they are different because food intolerances:

do not involve the immune system
are slower in onset
are not life threatening.

Symptoms of allergic reactions

For some people, eating a food with an allergen present or even having their skin come in contact with the allergen is enough to cause an allergic reaction.

The allergen can cause their immune system to overreact, causing symptoms that affect their breathing, stomach, gut, skin, heart and blood pressure.

Common symptoms are:

swelling of the lips, face and eyes
hives
tingling mouth
noisy or difficulty in breathing
cough
difficulty talking
dizziness
collapse.

Symptoms may be mild to severe. They may occur almost immediately after eating or, most often, within 20 minutes to two hours after eating.

Severe reactions, called anaphylaxis, are life threatening and can result in death.

Food intolerance symptoms

Symptoms like headaches, bloating, vomiting and diarrhoea are often common.

People can feel seriously unwell but they do not die from the intolerance.

A food intolerance is often due to the natural chemicals found in foods.

The most common foods to cause a reaction for people with a food intolerance are foods containing glutamate, amines and salicylates.
For example:

amines can be found in pineapples, bananas, vegetables, red wine, chocolate, citrus fruits and mature cheese
salicylates can be found in some herbs, spices, fruit and vegetables
glutamate can be found in tomatoes, soy sauce, mushrooms and some cheeses.

Coeliac disease

Coeliac disease (pronounced ‘seel-ee-ak’) is a common condition where the immune system attacks the body when gluten is eaten. Unlike allergies or intolerances, it can harm the intestines and cause serious long-term health problems. People with coeliac disease must follow a strict gluten-free diet, as even a tiny amount of gluten can cause harm.

Answer this practice question...

Food intolerances are different from allergic reactions because they A have a quick onset B are not life threatening C do not cause serious illness D cause anaphylaxis

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