Food allergies affect
nearly 6 percent
of Americans. Here’s how to know if you have one as well as how to manage it
if you do.
Food allergy basics
A food allergy
occurs when your immune system mistakenly thinks that a certain food poses a
threat to your body and releases
chemicals called histamines
to fight it off. These histamines trigger food allergy symptoms, which
include itching, swelling, hives, difficulty breathing, abdominal cramps,
vomiting, and diarrhea. In severe cases, food allergies can cause
anaphylaxis, a life-threatening reaction that requires immediate medical attention.
It's important to know the difference between food allergies and food intolerances. If you’re intolerant to a food, you have trouble digesting it.
That can produce symptoms such as bloating and gas, but it doesn’t involve
your immune system.
- MORE ON HEALTH & WELLNESS
- Gout is a serious and often misunderstood health condition
- How to make healthy living a family affair
- Your seasonal allergy survival guide
Foods and other substances that cause allergic reactions are called
allergens. Just
nine foods
are responsible for 90 percent of food allergies: Cow milk, eggs, tree nuts,
peanuts, shellfish, fish, wheat, soy, and sesame.
Peanuts, tree nuts, fish, and shellfish
commonly cause the most severe reactions. People with these allergies must
be especially careful not to eat even the tiniest quantities of these foods
and, in some cases, cannot even be in the same room without anaphylaxis.
Diagnosis
To determine whether you have a food allergy, your health care provider will
likely start with a physical and ask about your medical history and the
health history of your biological relatives. They also
will want to know:
• The foods you think are causing your symptoms
• Whether those symptoms always occur after eating the food
• Whether the food is cooked, raw, or both when symptoms appear
• How much of the food you have to eat for symptoms to occur
• How much time goes by between eating the food and the symptoms appearing
• Any other factors that may contribute to the symptoms
Your health care provider may also perform:
• A skin prick test
to determine if a certain food causes an allergic reaction
• A blood test to detect the presence of antibodies that can indicate a food
allergy
• An
oral food challenge test, in which you slowly eat increasing amounts of a food under medical
supervision as they monitor for a reaction
Your doctor may also ask you to keep a food diary and eliminate suspected
foods for a couple of weeks before reintroducing them one at a time to track
symptoms.
Treatment
Food allergies can’t be cured, but you can get
immunotherapy treatments
or
injections
to reduce your risk of having severe reactions.
For mild symptoms,
over-the-counter antihistamines
may provide relief. If you’re at risk for anaphylaxis, you should always
carry an
epinephrine auto-injector
or “Epi-pen” and make sure those around you know how to use it during an
emergency.
Management
Managing food allergies starts with
reading labels. By law, food packaging must list any of the nine major allergens if
they’re present. Labels may also include warnings like:
• “May contain” one of those foods
• Is “processed in a facility that also processes” one of those foods
• Is “made on equipment with” one of those foods
The last two warnings address the possibility of cross-contact, which
happens when an allergen unintentionally ends up in a product that’s
supposed to be safe.
If you live by yourself, you can prevent cross-contact by not having any
foods that you’re allergic to in your home. If you live with others and you,
or someone else, has food allergies, you should:
• Have separate storage, preparation, and dining areas for foods that are safe
for everyone and foods that aren’t.
• Cook safe foods first when you prepare a meal. If you can’t do that, cover
the safe foods so unsafe foods don’t splatter onto them.
• Thoroughly wash your hands with soap and water after handling a food to
which someone in your home is allergic.
• After every meal, thoroughly clean anything you use to cook or handle a food
to which someone in your home is allergic, as well as the surfaces
(stovetops, counters, tables) on which you prepare and serve food.
• Avoid sharing foods with others in your household.
To minimize the risk of cross-contact when dining out, call ahead to inform
the restaurant about your allergy and ask about cross-contact precautions
taken in their kitchen.
The whole dish
Depending on their severity, food allergies can range from mildly annoying
to life-threatening. If you suspect you have one, talk to a healthcare
provider about testing. Know what foods to avoid and be prepared for
emergencies. You also should make sure those close to you know what to do if
your food allergies cause you to experience a severe reaction.