The different types of allergies (asthma, hay fever, eczema and, more recently, food allergy) have increased dramatically over the past few decades – so much so that we now find ourselves in the middle of a possible “allergy epidemic”.
A child without any family history of allergies is now at approximately 15% risk of developing an allergic condition within the first few years. If one parent has an allergic condition, the child has a 40-50% risk of developing allergies.
If both parents are allergic, this increases to 60- 80%.
Having a sibling with allergies also carries an increased risk of developing an allergic condition.
There are many confusing messages on allergy prevention.
The following strategies have scientific backing and are currently recommended:
• Eat a wide variety of healthy foods.
• Don’t cut out on any food groups for the sake of allergy prevention. It will not reduce the risk of allergy in your child.
• Try eating two or more portions of oily fish per week. An alternative is to take omega-3 or fish oil supplements daily.
• Consider taking probiotics during the last trimester if your child is at risk of allergies (i.e. if there’s a family history of allergy in parents or siblings). Note, however, that there’s still much uncertainty about the best probiotic for this purpose and the most beneficial dose.
• Don’t smoke.
Feeding a new-born baby
• Breast milk is best and can help to prevent allergies; no formula milk is better than breast milk.
• A breastfeeding mother doesn’t have to eliminate any particular foods from her diet, except if the child is already showing signs of allergies. If this is the case, it’s best to check in with a healthcare provider.
• Breastfeeding for the first 4-6 months of life has the most benefit.
• Continuing to breastfeed while the first solids are introduced seems to have some benefit too.
• Prolonged breastfeeding (after 6 months) has no further allergy-prevention benefits (there are, of course, other benefits).
• In high-risk families, where the mother is unable to breastfeed exclusively during the first 4 months, a special less allergenic formula milk should be considered. Studies have shown some benefit in terms of allergy prevention. Discuss the choice of formula milk with your healthcare provider.
• In high-risk babies, consider giving a daily probiotic and prebiotic for the first 3 - 4 months (there’s no absolute proof that this is effective yet, but studies look promising).
• At this stage, there isn’t enough evidence to justify vitamin D supplementation for allergy prevention.
Introduction of solids
• Solids should be introduced when a child shows signs of readiness after 17 weeks of age (4 months).
• There’s no evidence that delaying the introduction of solids beyond 4 - 6 months of age prevents allergies. In fact, it may increase the risk.
• Start with reasonably low allergenic foods such as apple, pear, carrot, butternut and sweet potato for the first few weeks.
• Thereafter, you don’t need to hold back on any particular food group (even highly allergenic foods such as egg and nuts), as there’s no evidence that delaying their introduction reduces allergies. The recently published LEAP study, for example, showed that earlier introduction of peanut is probably better in terms of allergy prevention.
• If the child is already showing signs of allergies, or if there’s a strong family history of food allergy, the child should ideally be assessed by an allergist between 4-6 months of age. The doctor will check for evidence of food allergy and guide the introduction of “high-allergy” foods.
• There’s now evidence to suggest that keeping your baby’s skin in good condition can help to reduce eczema. Instead, it’s best to avoid soap products and to apply daily emollients (a good bland moisturiser with an emulsifying base or which contains an ingredient such as cetomacragol). Doctors don’t advise scented products or aqueous creams, as they may contain products that are too harsh for the sensitive skin.
• Once a specific allergy has developed, you can still reduce your symptoms by avoiding that specific trigger.
Reviewed by Prof Mike Levin, Head of Division of Asthma and Allergy at the University of Cape Town.
MBChB; FCPaed; MMed; PhD Diploma Allergology; EAACI UEMS Allergy exam, FAAAAI, FACAAI. March 2018.