When the body's immune system reacts abnormally to something a
person eats or drinks, it's known as a food allergy.
According to Food
Allergy Research and Education (FARE), it’s estimated that 15 million Americans have food
allergies. Children are more likely to experience food allergies. Approximately
1 in every 13 children in the United States lives with food allergies.
A food allergy may affect the skin, the
gastrointestinal tract, or the respiratory or cardiovascular systems. Many
types of foods can be allergens, but certain foods are much more likely than
others to trigger an allergic reaction.
According to FARE, eight foods are responsible for 90 percent of food
allergies. They are:
tree nuts (such as cashews or walnuts)
Symptoms of Food Allergies
Symptoms of food allergies may range from
mild to severe and they may come on suddenly or develop over several hours.
Because a person's immune system may
react to a very small amount of the allergen, food allergies are particularly
dangerous and potentially life threatening, especially if breathing is
affected. Because of this, people with asthma are at an increased risk for a
fatal allergic reaction to food.
Mild symptoms related to a food allergy
stuffy or runny nose
itchy, watery eyes
Severe symptoms of an allergic reaction
to food are:
difficulty breathing, including wheezing
swelling of the lips, tongue or throat
hives (an itchy, blotchy and raised rash)
dizziness or faintness
nausea or vomiting
A milk allergy is a reaction to whey or
casein, the proteins found in cow's milk. It’s not the same as lactose
intolerance. Milk allergies have been studied more than any other food allergy.
The bad news is that children with milk
allergies are much more likely to develop allergic reactions to other foods
including eggs, soy, and peanuts.
Most children with milk allergies also
develop one or more other atopic diseases such as asthma, allergic rhinitis, or
Egg allergies occur most often in
children and usually resolve at a very young age. However some people may
remain allergic to eggs for their entire lives.
A person may be allergic to a certain
protein in either the yolk or the egg whites. A person with an allergy to the
egg yolk may be able to tolerate egg whites and vice versa. Some people are allergic to both.
Children with peanut allergies rarely
grow out of their sensitivity to peanuts, so a peanut allergy is usually a
lifelong disorder. Because of this, peanut allergies are particularly serious. Accidental
exposure can occur at any time during a person's life. Though rare, a peanut
allergy may result in anaphylaxis. This is a severe allergic reaction that can
restrict breathing or cause cardiac arrest. Anaphylaxis requires immediate
medical attention in the form of a shot of epinephrine (EpiPen). A patient
should be watched for several hours after the shot to make sure symptoms don’t
Other Common Allergies
Less is known about soy and wheat
allergies than the more common allergies discussed above. Likewise, little is
known about fish, shellfish, and tree nut allergies except that, like a peanut
allergy, they are generally lifelong disorders.
Food allergies are usually diagnosed
depending on the severity of symptoms.
If a patient's symptoms are mild, a
doctor may recommend keeping a food diary to record all of the foods you eat or
drink to pinpoint the culprit. Another way to diagnose a mild food allergy is
to remove certain foods from the diet and then slowly reintroduce them to find
out if symptoms return.
In the case of more severe allergies,
skin or blood tests can identify egg, milk, nut, and shellfish allergies.
As with other types of allergies,
avoidance is most often the best medicine. Anyone with a food allergy should be
careful when purchasing food at a supermarket or restaurant to make sure there
are no traces of the allergen in a food or meal.
Milder symptoms may not require any
treatment at all, or a simple over-the-counter antihistamine may resolve the
For more serious allergic reactions, a
doctor may prescribe steroid medications. Steroids may have serious side
effects and shouldn't be used for more than a few days at a time.
Written by: Michael Kerr Edited by: Medically Reviewed by: George Krucik, MD, MBA Published: Nov 26, 2014 Published By: Healthline Networks, Inc.