Food allergies

Adverse reactions to certain foods can hamper your child’s life, but you can learn how to manage his allergies.

A mother's story

When Christopher Woodley was just 9 months old, he fought a daily battle with minor illnesses. Sinus problems and a constant postnasal drip were just part of his range of symptoms, and his mother, Hilary, a dietician who suffers from a variety of allergies was at a loss as to the cause.

Grommets were put in and his sinuses were washed out, but the illnesses continued. Even after he had both his adenoids and his tonsils removed, Christopher remained unwell.

At 18 months, Hilary’s sister, a doctor, expressed concern about Christopher’s breathing and indicated that he could have either tuberculosis or asthma. The TB test showed a reaction and his parents opted for X-rays for definite answers. The results showed that his lungs were enlarged.

Hilary turned to renowned allergist Dr Harris Steinman, and Christopher was diagnosed with a cow’s milk allergy. “He had tested for cow’s milk allergy, but the results were negative,” Hilary says. “This is common as many children before the age of 4 can be allergic to something and still test negative for it.”

Since he’s been off cow’s milk, Christopher has been healthy – even when the family were beset by colds and flu.

How food allergies affect infants

According to Dr Motala of the Allergy Society of South Africa (ALLSA), food allergy affects about 5% of infants in the first year. Studies have shown that approximately 12% of people develop adverse reactions to certain foods. Egg, cow’s milk, soy bean, peanut, wheat and nuts are the most common allergens in children.

Difference between food allergy and food intolerance?

What many people call a food allergy is, in fact, a food intolerance. Although both result in an adverse bodily reaction to a food ingredient, they are not the same.

According to Dr Adrian Morris of the Surrey Allergy Clinic, there are four types of adverse food reactions that can occur in infants and children.

Food allergy

A true food allergy sees an instant reaction. “These reactions may occur to minute amounts of the offending food in the diet. They depend on the bowel surface integrity and the individual’s ability to mount an abnormal immune response,” he says. True food allergies are rare.

Food intolerance

Food intolerance, on the other hand, is a non-immune response.

Dr Morris says these may involve food malabsorption due to intestinal enzyme deficiencies, adverse reactions to naturally-occurring chemicals in food such as salicylates or histamine, as well as reactions to preservatives, flavourants and colourants.

Spoiled food may release naturally-occurring toxins such as glyco-alkaloids in potatoes, resulting in food toxicity, while some food reactions are psychological and termed “food aversions”.

Symptoms of food allergies and intolerances may include swelling, vomitting and stomach pains. In extreme circumstances anaphylaxis, a severe and rapid allergic reaction, may occur and the allergy may prove fatal.

It is estimated that approximately one third of children and adults outgrow their allergies.

The importance of diagnosis

Diagnosis is important in order to manage the allergy or intolerance. In the past, allergy tests were performed through skin exposure. Scratches on the skin would be put into contact with different allergens to see which would cause a reaction. This test is still used particularly with non-food allergies.

Elimination is also often suggested. Foods are gradually eliminated and then reintroduced to pinpoint the cause of the allergy.

Christopher did a skin-prick test, and despite the fact he was already on antihistamines, still showed a reaction which confirmed the diagnosis.

RAST test

The RAST test is a blood test that identifies IgE (immunoglobulin) antibodies in the blood and can be used to diagnose certain allergies although not all children who experience allergic reactions test positive for the antibodies.

According to Dr John Pridgeon of Alcat, hidden food sensitivities cause and worsen some of today’s commonest and most incapacitating illnesses.

“The symptoms may not be noticed until long after eating the trigger foods, and usually many foods are responsible for the development of the different disease syndromes that affect each individual. Many food-sensitive patients will suffer puzzling symptoms and illnesses, and are chronically sick. Unfortunately, because of the delay, (between two hours and seven days after ingestion) these people are virtually unaware that foods have anything to do with their problem,” he says.

Alcat Food Sensitivity Blood Test

A new method for detecting food allergies is the Alcat Food Sensitivity Blood Test. It tests foods and chemical sensitivities, measuring changes in white blood cell sizes and numbers using sophisticated instrumentation and measuring around 40 000 cells for each food type, corresponding to around six million cells per patient test.

The test can be performed on children from 6 months of age. Alcat also tests for ADHD, which sometimes has a link to food intolerance.

The results grade the foods into four categories: foods that are safe, and which will then be rotated in the diet; two categories of food that should be avoided for at least three months; and foods that should be eliminated for six months or more.

“Once your immune system has ‘forgotten’ its sensitivities, the offending foods may then be safely reintroduced without causing an immune reaction,” says Dr Pridgeon.