To learn about the components of a food allergy, read the article What is a Food Allergy?

Updated article : October, 2023.

Most often food allergies result from combinations of genetics and environment (family medical history). If the two parents have allergies, the child has a 40–60% chance of developing them. If one parent has allergies, 20–40% chance. Finally, if the parents don’t have allergies, the child has a 5–10% chance.

Babies have a higher risk of developing food allergies when their parents, brothers or sisters:

• Have episodes of severe eczema with persistent patches;
• Have already been diagnosed with food allergies;
• Or have been diagnosed as asthmatic or suffer from seasonal allergies like hay fever.

This shows predisposition, family history of reactions to potential allergens. The foods with the highest level of allergens in children are:

• Products containing cow milk proteins;
• Soy;
• Eggs.

Wheat, corn and beef come next. Peanuts, nuts and fish & seafood follow, at smaller scales of sensitivity.

Research studying food allergies indicates no consensus about cross-reactivity often noted with cow milk protein, bovine protein (beef) and soya. Considering family history, when an allergic child is already present, you need to act on symptoms faster for another baby from the same parents.

As mentioned earlier in this post, however, it is not recommended (2023 update) to restrict the diet of a mother breastfeeding her new baby, even if there is a history of allergy or intolerance in the family. Restricting or delaying a newborn’s exposure to certain food in the breast milk could ultimately put it at greater risk of developing allergies, despite good intentions.

Besides the hereditary aspect, a baby can have an immature intestine with inadequate or excessive defences against proteins normally inoffensive for most people. This can explain an allergy occurring with early exposure to certain allergens before six months of age. The “allergen” protein makes the immune system react, and the body goes on the defensive producing antibodies (chemical substances) that circulate in the blood. This produces different clinical signs and symptoms.

To continue reading, click on the following link – Signs of a Food Allergy.