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Allergies Health Center

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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:

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:

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:

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

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