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Food Allergy, or Something Else?

It’s pretty common to have a reaction to a certain food, but in most cases it’s an intolerance rather than a true allergy. Why does it matter? Although they may have similar symptoms, a food allergy can be more serious.

These clues can help you figure out if it is an allergy or intolerance. A doctor can help you know for sure.

Food Allergy:

  • Usually comes on suddenly
  • Small amount of food can trigger
  • Happens every time you eat the food
  • Can be life-threatening  

Food Intolerance:

  • Usually comes on gradually
  • May only happen when you eat a lot of the food
  • May only happen if you eat the food often
  • Is not life-threatening

Shared Symptoms

A food allergy and an intolerance both can cause:

  • Nausea
  • Stomach pain
  • Diarrhea
  • Vomiting

Different Symptoms

When a food irritates your stomach or your body can't properly digest it, that’s an intolerance. You may have these symptoms:

  • Gas, cramps, or bloating
  • Heartburn
  • Headaches
  • Irritability or nervousness

A food allergy happens when your immune system mistakes something in food as harmful and attacks it. It can affect your whole body, not just your stomach. Symptoms may include:

  • Rash, hives, or itchy skin
  • Shortness of breath
  • Chest pain
  • Sudden drop in blood pressure, trouble swallowing or breathing -- this is life-threatening. Call 911 immediately.

 

Common Food Allergies and Intolerances

These triggers cause about 90% of food allergies.

The most common food intolerance is lactose intolerance. It happens when people can’t digest lactose, a sugar found in milk and dairy. Another kind of intolerance is being sensitive to sulfites or other food additives. Sulfites can trigger asthma attacks in some people.

What about a gluten allergy? While celiac disease -- a long-lasting digestive condition that’s triggered by eating gluten -- does involve the immune system, it doesn’t cause life-threatening symptoms.

Treatment for Food Allergy

Your doctor can find out if you have an allergy or intolerance. These things may help:

  • Keep a diary of the foods you eat and the symptoms you have
  • Stop eating some foods to help figure out which one is causing symptoms
  • Have allergy tests

If you have a food allergy, you'll need to stop eating the food altogether. .If you have a food intolerance, you’ll need to avoid or cut back on that food in your diet. For lactose intolerance, you can look for lactose-free milk or take a lactase enzyme supplement.

With a food allergy, you could be at risk for anaphylaxis, a life-threatening reaction. Ask your doctor if you need to carry an Auvi-Q or Epi-Pen (epinephrine shots) that you could give yourself in an emergency. If so, always carry two injections with you.   

How to Prevent Symptoms

  • Learn which foods -- and how much -- cause you to have symptoms. Either avoid the food or only have as much as you can without triggering symptoms.  
  • When you eat out, ask your server about how your meal will be prepared. It may not always be clear from the menu whether some dishes contain problem foods.
  • Learn to read food labels and check the ingredients for trigger foods. Don't forget to check condiments and seasonings. They may have MSG or another additive that can cause symptoms.

WebMD Medical Reference

Reviewed by Laura J. Martin, MD on October 25, 2012

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