Food Allergy

As many as two out of five Americans believe that they have allergies to certain foods. In point of fact, however, fewer than 1% have true food allergies. A food allergy occurs when the body's immune system reacts to otherwise harmless substances in certain foods. This is different from a food intolerance, which does not involve the immune system. While most food allergies are mild, in some cases they can cause anaphylactic shock, a serious, sometimes life-threatening, reaction. Food allergies affect mostly young children. With the exception of peanut allergy, the majority of children outgrow their food sensitivities.

Signs and Symptoms

Many people who think they have food allergies actually have food intolerances. Symptoms of a true food allergy usually involve the skin and intestines and generally begin just after eating and not longer than two hours following ingestion of the particular food. Common symptoms include: When the symptoms listed above are extreme, they can be life-threatening. Call a medical emergency response unit if you see the following signs of extreme allergic reaction (anaphylactic shock): Causes
In most cases, allergies occur when an individual who has a genetic sensitivity to certain allergens is exposed to the substance. Foods frequently responsible for food allergies include: Foods that may cause intolerance include:

Risk Factors


A comprehensive history will be taken to find out what symptoms you experience after eating and how soon after eating they occur. Your doctor will also want to know how often you have had the reaction and what type of medical treatment was needed. Even if your symptoms seem clearly related to a specific food, your doctor may still want to do some tests to be sure that you have a true food allergy and to verify the food or foods responsible for your allergic reaction.

The food causing the allergy can sometimes be identified by:

Preventive Care

Although there is no guarantee of success, guidelines from reputable health agencies suggest some steps parents can take to reduce their child's chances of having food and other allergies. If either or both parents have a personal or family history of allergy (for example, asthma, eczema, hay fever, perennial allergic rhinitis [allergy to animals, dust mites, or molds]) the following measures are recommended:

Treatment Approach

The goals of treatment are reduction of symptoms and avoidance of future allergic reactions. Once the particular food allergy is identified, the best way to accomplish this is by not eating that food. Treatment at the time of a reaction varies with the severity and type of symptoms. Mild or localized symptoms may subside without treatment. Antihistamines (available either by prescription or over the counter) are usually recommended to relieve mild itching, swelling, rash, runny nose, or headache. Soothing skin creams may provide some relief of rashes. Severe allergic reactions (anaphylactic shock) can come on suddenly and accelerate quickly; in this case, you must go to the hospital by ambulance immediately. In some instances, survival may depend on an injection of epinephrine (adrenaline). Self-administration of epinephrine is routinely taught tofood allergy sufferers and can be life saving. Avoiding the offending food is the best way to prevent future allergic reactions.



Nutrition and Dietary Supplements

Although it will be necessary to diligently avoid foods that provoke an allergic reaction, it need not restrict variety in your diet. Studies show that the vast majority of people are allergic to only one or two foods. However, you may be cautioned to be aware of the families of foods to which you are allergic. For example, if you are allergic to walnuts, you may also be allergic to pecans and almonds; an allergy to shrimp may also mean an allergy to crab.

Lactobacillus Acidophilus
L. acidophilus are bacteria that inhabit the intestines and vagina and protect against the entrance and proliferation of organisms that can cause disease. Some experts suggest that L. acidophilus may help to lower the risk of allergies, including food allergies.

Although scientific evidence is lacking, lipase (a digestive enzyme responsible for the breakdown of fat) has been used by trained clinicians to treat food allergies.

Vitamin C
Although the information to date is limited, some experts believe that vitamin C may be helpful for allergic conditions such as food allergies. This application needs further study, but may be related to the ability of vitamin C to improve immune function.


Herbal medicines have not been specifically tested for food allergies. There are a wide variety of herbs, however, that a qualified herbal specialist might consider to help treat your food allergies and your symptoms based on his or her clinical experience. Examples of some herbs such an expert might select are listed below. Each of these herbs might be considered because of its ability to treat either allergies in general or stomach symptoms: Herbs, like medications, may produce side effects or interact with other substances including drugs. They should, therefore, be used with caution and only under the guidance of a professionally trained and qualified herbalist.

Other Considerations

Women who have a food allergy or a partner with a food allergy may be able to reduce the risk of allergy in their child by avoiding common allergenic foods during pregnancy and nursing.

Prognosis and Complications

Food allergies may cause symptoms ranging from mild abdominal discomfort to life-threatening anaphylaxis. The avoidance of offending foods may be easy if the food is uncommon or easily identified. However, the successful avoidance of offending foods often requires strict reading of all package ingredients and detailed inquiries when eating away from home. Children may outgrow food allergies (particularly to milk or soy), but adults are unlikely to lose their allergies.


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