What is the difference between food allergy and intolerance.

Is your persistent belly pain and bloating from food allergies or food intolerances? Both can cause a physical reaction after eating certain foods, so it’s easy to confuse the two. But there are significant differences between food allergies and intolerances.

Here’s a comparison between food allergies and intolerances, including what causes them and how you diagnose and manage them.

What Is a Food Allergy?

A food allergy is an immune system reaction that happens after eating even a tiny amount of a particular food. When you ingest the food, your immune cells identify a protein in that food as harmful, even though it’s not. As your immune system attacks the protein, it triggers allergy symptoms that appear shortly after eating the food.

The symptoms can vary but commonly include:

  • Eczema (a type of skin rash).
  • Hives (an itchy, bumpy skin rash).
  • Itching, burning, or swelling around your mouth or tongue.
  • Sneezing, runny, or stuffy nose.
  • Stomach pains, nausea, or vomiting.
  • Swelling in your throat.
  • Difficulty breathing.

In rare cases, a food allergy can also trigger a life-threatening reaction called anaphylaxis. It causes difficulty breathing and a dangerous drop in your blood pressure. If you have any severe symptoms after eating, it’s crucial to call 911 immediately because anaphylaxis is serious and possibly deadly.

These nine foods account for food allergies in most people:

  • Milk.
  • Soy.
  • Wheat.
  • Eggs.
  • Peanuts.
  • Tree nuts (walnuts, almonds, pecans).
  • Fish.
  • Shellfish (lobster, shrimp, crab).
  • Sesame.

Never Miss a Beat!

Get Healthy Tips Sent to Your Phone!

Message and data rates may apply. Text the word STOP to opt out and HELP for help. Click here to view the privacy and terms.

Food Intolerance and Bloating

Food intolerance doesn’t affect your immune system, but it can still cause a physical reaction. Digestive symptoms like bloating, upset stomach, or diarrhea are common. Food intolerances might also cause non-digestive symptoms like skin rashes, migraines, or brain fog, but they don’t cause anaphylaxis.

Food intolerances often happen when your body can’t make certain enzymes needed to digest food — hence the digestive symptoms. Lactose intolerance is a classic example. With this lactose intolerance, you don’t produce lactase, the enzyme that breaks down milk sugar.

Lactose intolerance causes gas, bloating, belly pain, and diarrhea shortly after eating or drinking dairy foods. Please note that some individuals with lactose intolerance can consume small amounts of aged cheese (Cheddar, Swiss, and Parmesan) or probiotic-rich yogurt (like Greek yogurt) as the bacteria/yeast used in production produce some lactase enzyme.

Some people may wonder “Why am I all of a sudden lactose intolerant?” The answer: This and other intolerances can develop as you age. That’s different from food allergies, which typically start in young children. Also, temporary intolerance can occur after intestinal infections.

Does Gluten Intolerance Cause Bloating?

Gluten intolerance, also called non-celiac gluten sensitivity, is another food intolerance that causes GI symptoms. With this, you have difficulty digesting gluten, the protein in wheat, rye, and barley.

Gluten intolerance is different from celiac disease, in which the body’s reaction to gluten damages the lining of the small intestine. Gluten intolerance causes bloating, gas, and other digestive symptoms. Some people also report migraines and difficulty concentrating after eating gluten.

Food intolerances like this are fairly common and can involve a wide range of foods. With a food intolerance, you might be able to eat small amounts of the offending food without symptoms. That’s different from an allergy, where even a small bite will trigger a reaction.

Is It a Food Allergy or Food Intolerance?

If you notice symptoms after eating certain foods, it’s wise to keep a food and symptom journal to confirm it. Then talk to your doctor to see if you should have food allergy testing. An allergist can diagnose a food allergy with blood tests or skin prick tests to see if you react to specific proteins.

Food intolerances are often trickier to diagnose. There are tests for lactose intolerance and celiac disease, but not for non-celiac gluten sensitivity or intolerance of many other food compounds. Often, a doctor or dietitian will review your symptoms and recommend an elimination diet to see if your symptoms improve.

Can You Cure a Food Allergy or Intolerance?

Currently, there is no cure for food allergies or intolerances. With a food allergy, it’s essential to avoid the food you’re allergic to because of the (usually small) risk of anaphylaxis. It’s not crucial to avoid offending foods with food intolerances, although doing so will make you feel better.

You may also be able to manage a food intolerance with digestive enzymes. These are pills or drops you take just before eating the food you’re sensitive to. They contain the enzymes your body can’t produce, making it easier to digest the offending food. For those who can’t tolerate any form of animal milk, plant-based milk is a reasonable alternative. Most currently available plant-based milk are fortified with minerals and vitamins, but protein content may vary, hence it is important to read the labels.

If your doctor diagnoses you with a food allergy or intolerance, ask for a referral to a registered dietitian. They can educate you about which foods to avoid and help you examine food labels to identify allergenic ingredients. They can also help you find appropriate substitutes to ensure your diet is nutritionally complete.

Food Allergy Research & Education. Food Allergy 101. LINK

F1000 Research. Recent Advances in Understanding Non-Celiac Gluten Sensitivity. LINK

About UPMC

Headquartered in Pittsburgh, UPMC is a world-renowned health care provider and insurer. We operate 40 hospitals and 800 doctors’ offices and outpatient centers, with locations throughout Pennsylvania, Maryland, New York, West Virginia, and internationally. We employ 4,900 physicians, and we are leaders in clinical care, groundbreaking research, and treatment breakthroughs. U.S. News & World Report consistently ranks UPMC Presbyterian Shadyside as one of the nation’s best hospitals in many specialties and ranks UPMC Children’s Hospital of Pittsburgh on its Honor Roll of America’s Best Children’s Hospitals. We are dedicated to providing Life Changing Medicine to our communities.