Eczema - an immune system disorder

Eczema, also called atopic dermatitis, is an immune system disorder. It's caused by a problem with the skin barrier, skin dryness and inflammation. People with eczema often have other allergic conditions, including food allergy, but food allergy does not cause eczema.

Common triggers of eczema flares

Eczema affects the skin, causing redness, itching and sometimes infections. When eczema gets worse, it is called an eczema flare. Common triggers of eczema flares include dry climate, overheating, exposure to irritants (such as sand or dirt), scratching, allergens (such as dust mite) and bacterial skin infections.

Managing eczema well

You can manage eczema well by maintaining, protecting and treating skin by:

• putting moisturiser on at least twice a day (avoiding those that contain food products)
• using a non-soap based wash or oil in the bath or shower
• avoiding soap and washes that produce bubbles or foam, which damage and dry out the skin
• avoiding known triggers (including foods if confirmed) and irritants
• using anti-inflammatory creams and ointments, such as topical steroids
• treating bacterial skin infections with antibiotics, or using bleach baths if infections are frequent
• using medicines to reduce inflammation, if prescribed for severe eczema

Food allergy is more common in babies with eczema and a family history of allergy

Around 30 in 100 babies in these groups develop food allergy compared to only 10 in 100 in the general population. There is some evidence that managing eczema well during infancy may reduce the chance of a baby developing food allergy.

When a child has eczema and food allergy, food allergy may trigger eczema, but is not the cause of their eczema

Most food allergy causes hives, vomiting and irritability within 30 minutes of eating. Food allergy only occasionally results in delayed eczema flare ups.

Results of skin tests or blood tests for food allergy do not predict food(s) that are making the eczema worse

In New Zealand, a specialist doctor or nurse with training in allergy should recommend and interpret any food allergy tests that your child has. 

Only try a 'food exclusion diet' if your child's eczema does not improve with treatment, and always with medical supervision  

Before considering a 'food exclusion diet', follow the steps in 'Managing eczema well' above.

Confirming that food allergy is causing delayed eczema only needs short-term food exclusion. A health professional (doctor or nurse) with allergy training should always supervise food exclusion diets. If the specialist recommends continuing food exclusion longer term, children should also see a paediatric dietitian with specialised knowledge of food allergies.

Taking foods out of your child's diet without using the right substitutes (for good nutrition) can cause malnutrition and poor growth

Also, if your child has been regularly eating a food without signs of allergy, taking that food out of their diet can result in them developing a new allergy to that food.