Is it an Allergy or a Food Intolerance?

Do you know the difference between being sensitive to a food and being allergic to it? One can be deadly. Learn how to distinguish between the two.

Telling the difference between a food allergy and a food intolerance isn't always easy. Sometimes, the symptoms are the same. For example, milk (lactose) intolerance and a mild food allergy can both cause nausea, gas and vomiting. If you have symptoms after eating certain foods, see your doctor.

Food intolerances vs. food allergies
Food intolerances are common. For example, about one in 10 Americans are lactose intolerant. On the other hand, only about one in 100 have food allergies.

If you have a food allergy, your immune system reacts to the food by triggering an allergic chemical reaction into your bloodstream. Mild food allergies cause nausea and vomiting. Severe reactions include hives, wheezing and swelling of the lips, face, tongue and throat. These can be life threatening. In young children, food allergies can also cause eczema (a type of skin rash).

A food intolerance happens when your body reacts to a particular food. The immune system is not involved. Symptoms usually come on more slowly than with food allergies. They are usually limited to the stomach and aren't life threatening.

The most common food allergens are:

  • Milk
  • Eggs
  • Peanuts
  • Tree nuts
  • Fish
  • Shellfish
  • Soy
  • Wheat

Food intolerances are usually caused by:

  • Milk and other dairy products
  • Sulfites
  • Food dyes
  • MSG

To identify food problems, keep a diary. Write down what and when you eat. Note if a certain food always causes a reaction and when your symptoms appear. Also note if other people who eat the same food get sick. Your doctor may also do allergy testing or run lab tests to find out the cause of your symptoms.

Next steps
If an allergy or intolerance is found, your doctor will tell you how to avoid that food in the future.

If you are lactose intolerant, your doctor may suggest lactase tablets. You may be able to eat a limited amount of certain dairy foods. A nutritionist can recommend a calcium-rich, lactose-free diet. This will include lots of greens and fish, as well as vitamin D pills.

With severe allergies, you are usually given antihistamines. Your doctor may also prescribe an adrenaline pen. You can use this to inject yourself if you have a reaction. Never go anywhere without your medication.




© UnitedHealthcare