The difference between food allergies and food intolerances in kids

By Associate Professor Alberto Pinzon Charry

Paediatric allergist and immunologist in Woolloongabba, Brisbane

If your child reacts to a food, it’s natural to worry. Is it an allergy? An intolerance? Or something else entirely?

These terms are often used interchangeably, but they’re quite different, and understanding the difference is important for your child’s safety and wellbeing.

What is a food allergy?

A food allergy involves the immune system. The body mistakenly treats a food as harmful and reacts to it – sometimes very quickly, even after a small amount.

Common symptoms include:

• hives or skin rash
• swelling of the lips, face or eyes
• vomiting
• breathing difficulties or wheezing

In some cases, a food allergy can lead to anaphylaxis, a serious reaction that requires urgent medical attention.

What is a food intolerance?

A food intolerance does not involve the immune system. Instead, it’s usually related to how the body digests or processes certain foods.

Symptoms tend to be less severe, but can still be uncomfortable. They often affect the gut and may include stomach pain, bloating, wind or diarrhoea.

Unlike allergies, food intolerances are usually dose related. This means your child might tolerate a small amount of a food, but react if they have more.

What’s the main difference?

The simplest way to think about it is:

• Food allergies affect the immune system and can be serious.
• Food intolerances affect digestion and are usually less severe.

Another key difference is how quickly symptoms appear. Allergic reactions are often rapid, while intolerances can take longer to develop.

A couple of everyday examples

A practical way to understand the difference is to look at how reactions show up in real life.

If your child eats a small amount of peanut and quickly develops hives or swelling, this is more likely to be a food allergy.

If they drink milk and later complain of stomach pain or bloating, this is more likely to be a food intolerance, such as lactose intolerance.

Why getting the right diagnosis matters

Knowing whether your child has an allergy or intolerance helps guide the right care.

Food allergies usually require strict avoidance and, in some cases, an allergy action plan or emergency medication.

Food intolerances are often managed by adjusting the amount or type of food, rather than avoiding it completely.

When should you seek help?

If you’re unsure about your child’s reaction, it’s best not to guess.

It’s worth seeking medical advice if your child has repeated reactions to a food, or if symptoms involve the skin, breathing or swelling. It’s also important to speak to a professional before removing foods from your child’s diet long term, as this can affect their nutrition and growth.

How a paediatric allergist can help

A paediatric allergist can assess your child’s symptoms, confirm whether it’s an allergy or intolerance, and provide a clear plan moving forward.

For many families, this brings reassurance and confidence – knowing what to avoid, what’s safe, and how to manage any future reactions.

The bottom line

Food allergies and food intolerances can look similar, but they are very different conditions.

Understanding the difference helps you make informed decisions and ensures your child gets the right care.