Allergy or Intolerance?

It’s almost impossible to hold a dinner conversation with a group of people without someone mentioning some type of reaction to a certain food. But in many cases, that reaction can be considered a food intolerance rather than a food allergy.

That might not seem like a big deal because the symptoms are pretty similar. However, it is important to understand because a food allergy can be much more serious.

Here’s the difference.

A food allergy is an immune system response. That means there is something in the food, usually a protein, that the body mistakes as harmful and creates a defense system (antibodies) to fight it. In other words, the antibodies are fighting off the invading food protein. Peanut allergies are the most common type.

A food intolerance is a digestive system issue. It occurs when something in a food bothers, or irritates, a person’s digestive system. It also happens when the digestive system is unable to break down or digest the food. You might know of someone who is lactose intolerant, which means the body has a difficult time processing lactose, which is found in dairy products. That is the most common food intolerance.

Here are some clues to the difference between a food allergy and a food intolerance:

Food Allergy:  Food Intolerance:
Usually comes on suddenly Usually comes on gradually
Needs only a small amount of food to trigger Needs a lot of food to trigger
Reaction occurs every time the food is eaten Needs to be eaten often                                                                  
Can be life-threatening Makes you feel uncomfortable but is not life-threatening


While food allergies and food intolerances can both cause nausea, stomach pain, diarrhea and even vomiting, food allergies also trigger much more serious symptoms. Those can include itchy skin, rash or hives, chest pains and even shortness of breath.

- Frank Graff

Frank Graff is a producer/reporter with UNC-TV, focusing on North Carolina Science Now, a weekly science series that airs Wednesdays, beginning in August 2013, as part of North Carolina Now on UNC-TV. In addition to producing these special segments, Frank will provide additional information related to his stories through this North Carolina Science Now Reporter's Blog!


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