Allergy prevention strategies

Allergies of all sorts (asthma, hay fever, eczema and more recently food allergy) have increased dramatically over the past few decades, and we 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 is at 40-50% risk of allergies, and if both parents are allergic, this increases to 60-80%. Having a sibling with allergies also carries an increased risk of allergic conditions developing.

There are many confusing messages on allergy prevention- the following are the ones with scientific backing that we currently recommend. These strategies are currently the best we can offer to help reduce the chance of allergies developing, but are of course not a 100% guarantee against allergies!

Allergy prevention strategies during pregnancy

  • Eat healthily; eating a wide variety of foods is beneficial
  • No need to cut out on any food groups for the sake of allergy prevention- it does not reduce allergy in the offspring
  • Try eat 2 or more portions of oily fish per week
  • Consider taking probiotics in the last trimester if your child is at risk of allergies (ie if there is a family history of allergy in parents or siblings). However, the best probiotic and optimal dose are still under investigation
  • Don’t smoke

Allergy prevention strategies when feeding the newborn

  • Breast milk is best and has allergy prevention properties- no formula milk is better than breast milk
  • The breast feeding mother does not have to eliminate any particular foods from her diet except if the child is already showing signs of allergies (e.g. eczema)- then discuss with your healthcare provider
  • Breastfeeding for the first 4-6 months has the most benefit
  • Continuing to breastfeed whilst the first solids are introduced seems to have some benefit too
  • Prolonged feeding over 6 months has no further allergy prevention properties (but of course has other benefits)
  • In high risk families, only if the mother is unable to breast feed exclusively during the first 4 months, consider using a “hypoallergenic” formula milk. Some studies have shown some benefit in allergy prevention. Others have not. Please discuss the choice of formula milk with your healthcare provider
  • In high risk babies consider giving a daily probiotic (harmless, healthy bacteria) and prebiotic (indigestible foods which stimulate the growth of healthy gut bacteria) for the first 3-4 months.  There is no absolute proof of the right dose and type of pre- and probiotics yet.
  • We do not yet have enough evidence for vitamin D and fish oils for allergy prevention

Allergy prevention strategies when introducing solids

  • Solids should be introduced when the child shows signs of readiness after 17 weeks of age (4 months)
  • There is no evidence that delaying solids beyond 4-6 months of age prevents allergies: in fact it may increase allergies
  • Start with reasonably low allergenic foods such as apple, pear, carrot, butternut, sweet potato for the first few weeks.
  • Thereafter you do not need to hold back on any particular food group- even highly allergenic foods such as egg and nuts- as there is no evidence that delaying their introduction reduces allergies. The recently published LEAP study, for example, showed that earlier introduction of peanut is probably better for allergy prevention.
  • HOWEVER, if the child is already showing signs of allergies- e.g. eczema, or if there is a strong family history of food allergy, then the child should ideally be assessed by an allergist between 4-6 months of age to check for evidence of food allergy and to guide the introduction of “high allergy” foods.

Other allergy prevention strategies

  • There is now evidence that keeping your baby’s skin in good condition can help reduce eczema: this can be done by avoiding soap products and by applying daily emollients (a good bland moisturiser containing ingredients such as cetomacragol or emulsifying base.) We do not generally advise scented products or so-called aqueous creams as they may contain products that are too harsh for the sensitive skin.