Food allergy and intolerance
Contrary to popular belief, food allergies are rare. Most reactions to food are a food intolerance. The symptoms usually affect three main sites of the body - the skin and the respiratory and digestive systems.
Allergy
Allergies are an over-reaction of the body’s immune system to a specific component, usually a protein. These proteins may be from foods, pollens, house dust, animal hair or moulds and are known as allergens. The word ‘allergy’ means that the immune system has responded to a harmless substance as if it were toxic.
Food intolerance
Food intolerance is a pharmacological reaction that some people have after eating or drinking; it is not an immune response. Food intolerance has been associated with asthma, Chronic Fatigue Syndrome and Irritable Bowel Syndrome (IBS).
Food intolerance is much more common than food allergy.
Symptoms of allergy and intolerance
The symptoms to a food allergy or intolerance are often difficult to distinguish. As the symptoms can also be caused by other conditions, medical diagnosis is always needed.
Symptoms of food intolerance
Symptoms of food intolerance may be immediate or delayed and are often triggered only after a threshold level of exposure is reached. They can include:
* Nervousness, tremor
* Sweating
* Palpitations
* Rapid breathing
* Headache, migraine
* Diarrhoea
* Burning sensations on the skin
* Tightness across the face and chest
* Allergy-like reactions due to histamine and other amines in some foods
* Asthma from food containing benzoates, salicylates, MSG and sulphite derivatives.
Symptoms of food allergy
The onset of symptoms from food allergy tend to be more immediate and can be life-threatening. Common symptoms include:
* Itching and burning and swelling around the mouth
* Runny nose
* Skin rash and hives, eczema, urticaria (skin becomes red and raised)
* Diarrhoea, abdominal cramps
* Breathing difficulties, including wheezing and asthma
* Vomiting, nausea
* Life-threatening anaphylaxis.