Food allergies

When a child’s immune system reacts to a particular food that he eats, he is said to suffer from a food allergy. Some allergies are permanent and very serious. A child with a known allergy to a particular food must never eat that food. It’s important to always take allergies seriously.

Some children may not be able to tolerate certain foods, but are not necessarily allergic to them. This is known as a food intolerance. The difference between food intolerance and food allergy is that food intolerances do not trigger an immune system reaction.

Is my child at risk of developing a food allergy?

A child is at greater risk of developing a food allergy if:

  • A member of his immediate family (mother, father, brother, or sister) has an allergic disorder.


  • The child suffers from severe eczema (shows signs of eczema most of the time).

Talk to your doctor.

Preventing allergies

In the past, it was recommended that parents wait until their babies had reached a certain age before introducing foods more likely to cause allergies. We now know that it’s best to introduce these types of foods at the same time as other solids (see A word about food allergies).

Don’t hesitate to consult a doctor if you have concerns.

How do I recognize allergies?

Information to which you should pay special attentionCall 9-1-1 if your child develops

  • Red patches on the skin
    AND one or more of the following:
  • Sudden and severe change in her general condition (e.g., irritability, drowsiness, loss of consciousness)
  • Swollen lips or tongue
  • Difficulty breathing
  • Sudden vomiting

She could be having a severe allergic reaction.

An allergic reaction can be sudden and severe, or it can be delayed.

Sudden and severe reactions (known as anaphylaxis) usually occur anywhere from a few minutes to two hours after eating the food in question. Such reactions are rare. See the red box (page 573) for the most common symptoms.

Delayed reactions can occur several days after eating the food in question. They are harder to diagnose. The most common symptoms include diarrhea, blood in the stools, and excessive irritability.

Any child can experience these symptoms at times, but they last longer in children with allergies. If you suspect that your child has a food allergy, stop giving him the food in question and consult a doctor.

Breastfed babies and allergies

There is no evidence linking the food breastfeeding mothers eat with the risk that their babies develop food allergies. Even if other members of the family have food allergies, you don’t need to stop eating allergy‑causing foods when you’re breastfeeding.

Babies are not allergic to breast milk, since it is perfectly adapted for their intestines. In rare cases, however, some babies may have an allergy to protein from a food their mother is eating that passes through their milk. Such proteins can come from a variety of foods, most often dairy products.

If your breastfed baby has certain symptoms (e.g., excessive crying, blood in stools, repeated refusal to feed), she may be intolerant or allergic to something you eat (see How do I recognize allergies?).

What to do?

If your baby reacts to your breast milk after you eat a particular food, he will feel better as soon as you eliminate it from your diet, but will react if you eat the same food again. Try proceeding by elimination to see whether your baby is allergic:

  • Stop eating the suspected food for 7 days.
  • Keep an eye on your baby’s behaviour.
  • If your baby is feeling better after 7 days, try eating the food in question again.
  • Keep an eye on your baby’s behaviour.
  • If the symptoms reappear, it means your baby is reacting to that particular food. Refrain from eating it.
  • If you need to make changes to what you eat, consult a nutritionist. She can advise you.

If there is no real improvement after you eliminate the food, it’s best to consult a doctor.

Severe allergies

Information to which you should pay special attentionIf your child has an epinephrine injector (e.g., EpiPen®), make sure you know when and how to use it. Explain the allergy symptoms to babysitters and post the emergency procedure to be followed in a visible location. Have your child carry a card or wear a bracelet (e.g., MedicAlert®) indicating her allergy.

If your child has a severe allergy, you will have to be very vigilant. If you buy prepared meals, read ingredient lists carefully to be sure they don’t contain the product your child is allergic to. When dining out, ask what’s in the dishes you order for your child.

For more information contact Allergies Québec at 1-800-990-2575 / 514-990-2575 or visit

Allergic disorder: An allergy-related problem such as a food allergy, asthma, eczema, or allergic rhinitis.

Immune system: Organs and mechanisms that allow the body to fight against infections.