FOOD ALLERGIES

SERIOUS LIFETHREATENING ALLERGIC REACTIONS ARE REFERRED TO AS AN ANAPHYLACTIC SHOCK.

Nutrition is very important to a healthy life, but many people are faced with omitting certain foods from their diet due to allergic reactions to these foods. A food allergy is quite different from food intolerance, which will be discussed in a future issue of Great Health GuideTM. A food allergy is an immune response to a specific protein within that food. The body reacts to this protein, believing it to be foreign and harmful.

SIGNS AND SYMPTOMS.

The allergic symptoms can include breathing problems, swelling of the mouth, lips, tongue and larynx, swelling of eyes and face, stomach pain, vomiting, hives or red welts anywhere on the body, dizziness and changes in blood pressure. While some of these signs and symptoms may appear in a mild form initially, continued exposure to the allergen will increase the severity of the allergic reaction. In severe cases, it may be a life threatening reaction due to restricted airways and an increased heart rate requiring hospitalization. In some cases only a very small amount of the actual food may cause serious life-threatening allergic reactions.

WHAT FOODS MAY CAUSE A PROBLEM?

There are many foods that trigger allergic reactions. The main culprits are egg, cow’s milk, peanuts and tree nuts such as Brazil nuts, almond and cashew, several seeds such as sesame, wheat, rye and oats. Certain species of fish can be a trigger but often shellfish (crabs, prawns, oysters etc.) are the major concerns.

It is not just the foods that contain high protein but many fruits and vegetables are also a problem. Many are favourites such as strawberries, kiwifruit, mango, oranges and bananas. These foods may have been able to be eaten in the past but allergies can develop at different times.

CAN A FOOD ALLERGY BE CURED?

While there is treatment available for an allergic reaction to a bee or wasp sting, at present there is no cure for a food allergy. However children often ‘outgrow’ the food allergy to cow’s milk and eggs as they become adults. Thus the body has become immune to the allergen and as adults, they can eat moderate amounts of the problem food. However most adults seem to be very reluctant to eat foods that caused problems in childhood.

HOW CAN FOOD ALLERGIES BE TESTED?

Many of the allergic reactions may only be mild or moderate and patients do not think there is any need to see a doctor. A few hives, redness and itch or a slight swelling of the lips are ignored. These are the early signs of an allergic reaction to a food. Often it is difficult and hard to work out what has caused the problem as the milder symptoms may not show immediately and may be delayed for 24-48 hours later.

However it is very important to have all food allergies diagnosed by an allergy specialist, using a Skin-Prick Test. This involves placing a drop of a serum that contains the allergen onto the patient’s forearm or back and a small needle prick is made so the allergen goes slightly under the skin’s surface. These tests may not always confirm the suspected food. Blood tests are a less common method of diagnosing food allergy, but they are much more expensive and not necessarily more accurate. Blood test are used to help confirm a

Skin Prick Test or when a serious allergy is suspected. In this case an allergen is not tested on the patient as in the Skin Prick Test, but placed in contact with patient’s blood in a laboratory dish; if the patient is sensitive to that allergen, the patient’s blood containing antibodies will react with the allergen and cause the blood to coagulate.

SUMMARY OF FOOD ALLERGY:

is different from food intolerance can cause life threatening symptoms is caused by many and various common foods can be tested for with Skin Prick Test can not be cured In the next issue of Great Health GuideTM, Food Allergy Part 2 will discuss treatments for severe allergic reactions, such as using an EpiPen® (epinephrine injection) Auto-Injector. However education is the key and vigilance will keep the family safe.

Helen Dodd BSc. BPharm. PhD, is a retired pharmacist, continuing to provide information and education on nutrition and diseases that affect modern society. Helen may be contacted via GHG.