You can get an allergy to any food, including broccoli, but it isn’t as common as other food allergies.

Salicylate allergy

Symptoms of a broccoli allergy usually mean that you’re sensitive to salicylates, which is a natural chemical that can be found in plants like broccoli.

Some people may be sensitive to even small amounts of salicylates. You may also have symptoms when eating other foods with salicylates like:

  • apples
  • avocados
  • bell peppers
  • blueberries
  • coffee
  • cucumbers
  • ginger
  • nuts
  • okra
  • raisins
  • strawberries
  • tea
  • zucchini

High doses of salicylates are also found in medicines including aspirin and Pepto-Bismol.

Pollen food syndrome

Some people are allergic to broccoli because it contains proteins that are similar to those in a kind of pollen that they’re allergic to. This is called pollen-fruit allergy syndrome (or oral allergy syndrome).

The Mayo Clinic notes that if you’re allergic to mugwort pollen, you may also react to broccoli and other plant foods. This is a rare cause of a food allergy from pollen.

An allergy to broccoli or other foods happens when your immune system mistakenly thinks the food is harmful. Eating even a tiny amount of the food can trigger an immune response.

This means that your immune system makes antibodies (chemical messengers) against the food. The antibodies signal your body to attack the food the next time you eat it. Your body “fights” the food just like it would fight a virus or bacterial infection.

This causes an allergic reaction. Symptoms of an allergy to broccoli are similar and as varied as other types of food allergies.

Reactions include:

  • mouth tingling
  • itching
  • coughing
  • sneezing
  • runny nose
  • lip or face swelling
  • wheezing
  • nausea
  • vomiting
  • dizziness
  • hives or skin rash

Some people may get a serious allergic reaction called anaphylaxis. This can be life-threatening. You may experience:

  • difficulty breathing
  • throat tightening
  • swelling
  • dizziness
  • low blood pressure
  • fainting

A food intolerance is different from a food allergy. It involves your digestive system, not your immune system.

You can have a food intolerance to broccoli and other foods with salicylates.

Your symptoms will likely be different from an allergic reaction. You may get:

  • stomach pain
  • cramping
  • gas
  • bloating
  • diarrhea
  • fatigue

If you have a food intolerance to broccoli it’s still possible you experience some symptoms that are similar to an allergy. The symptoms most often experienced are hives or rashes.

Your family doctor or allergist can find out if you’re allergic to broccoli. They will typically start by taking a health and family history, and asking about your symptoms.

You may need a prick or scratch allergy test to get a diagnosis.

This test will happen in your doctor’s office and only takes a few minutes. Your doctor will make a small, painless scratch on your arm. A small amount of broccoli or broccoli extract is put on the scratch.

If you have a reaction like redness or swelling, you may be allergic. Food intolerances don’t cause a reaction on the skin in a scratch test. If you believe it’s an intolerance, your doctor may send you to a dietitian.

If you’re allergic to broccoli, you’ll need to avoid eating broccoli. Even cooked or boiled broccoli can cause an allergic reaction in cases of true food allergy.

You may also have to avoid any other foods that share the same allergen.

Antihistamines

Treatment for a broccoli allergy includes antihistamine medications to help manage symptoms.

There are over-the-counter and prescription options for antihistamines. Formulas, active ingredients, and strengths vary.

Epinephrine

If your allergy is severe, you should also carry an epinephrine pen with you at all times. This injectable drug can help stop a serious allergic reaction like anaphylaxis.

In the case of a life-threatening allergy to salicylates, ideally you should keep an epinephrine pen in your home, car, bag, and at your place of work or school.

Salicylate-free diet

People who are allergic or sensitive to broccoli and salicylates in foods may have to avoid a long list of plant foods in order to lessen their symptoms. This can affect your health, both physically and mentally.

One study looked at 30 diets that were low in salicylates. The researchers found that eating a diet low in salicylate foods could lead to a deficiency in some important vitamins and minerals.

You may not get enough of these nutrients:

  • calcium
  • potassium
  • iodine
  • vitamin C
  • vitamin D
  • vitamin E
  • alpha-linolenic acid
  • fiber

Supplements and creative meal planning

To combat nutritional deficiencies, it’s important to take vitamin and mineral supplements if you’re cutting out foods with salicylates in them.

Ask a doctor or nutritionist about the best supplements for you and when to take them. A registered dietitian can help you with food and meal planning ideas to meet your nutrition needs.

Probiotics

Some studies found that taking probiotic supplements may help reduce food allergy symptoms. More research is needed on this kind of treatment.

Talk to your doctor about adding probiotics to your diet and daily supplement plan.

You can be allergic to broccoli, though it’s not very common. It’s much more likely to have a food allergy to other foods, such as peanuts, dairy, and wheat.

If you’re allergic or sensitive to broccoli you may also have symptoms when you eat other vegetables and fruits that are high in the natural chemical salicylates. Some drugs like aspirin contain high amounts of artificial salicylates. You may also be allergic to them.

The only way to prevent an allergic reaction to broccoli is to avoid eating it. Treatment for allergy symptoms includes antihistamines and an epinephrine pen.

Avoiding broccoli and other foods can cause low levels of some vitamins and minerals. Speak to your doctor about making up for any nutrients you’re lacking.