Can we prevent food allergies?

Allergies, for example eczema and reactions to foods such as peanuts and eggs, are on the rise. Over the past two decades the number of hospital admissions for severe allergic reactions (anaphylaxis) has increased six-fold, and as many as seven per cent of young people in the UK now have a food allergy. Could this be because of well-meaning advice given 20 years ago?

When I was a young mother, I mentioned at a postnatal group that I had mashed a bit of tuna and baked beans into my hungry four-month-old’s apple purée. There was much tutting and I was told that babies shouldn’t have complex proteins until at least six months. Sheepishly, I put him back on plain puréed fruit or veg. But recent research suggests that my action may have been OK.

Until the 1980s, it was common to start babies on solid food at around four months. Then the advice changed. But what is the connection between when you feed your child solids, having eczema and food allergies? According to Professor Gideon Lack, paediatric allergy specialist at King’s College London, allergies typically develop if a child is exposed to an allergen, such as peanuts, before they get exposed to that same allergen through the gut (ie, by eating it), as food particles can penetrate the skin barrier and set up an abnormal immune response. Research suggests foods that a baby first experiences by mouth are recognised as ‘friend’, while those first encountered through the skin may be classed as ‘foe’, potentially leading to an allergic reaction when next encountered. Lack’s research shows that ‘early consumption progresses the immune system towards a tolerant response’. His team showed that introducing small amounts of peanut butter to the diet of babies aged between four and 11 months old reduced peanut allergies by more than

80 per cent, compared to those who avoided them. He fears that delaying introduction of such food ‘is harmful’.

Lack also ran a study comparing the introduction of solids at six months to the introduction of potentially allergenic foods (egg, milk, peanuts, fish, wheat and sesame) at three months. He found that there was a significant reduction in food allergy prevalence in those children at risk of allergies who were introduced to allergenic foods earlier.

The British Society for Allergy and Clinical Immunology gives the following guidance…

★ If a child has eczema, stick to the prescribed regime and maintain a good skin barrier.

★ Consider introducing solid foods from four months for children at higher risk of allergies, including cooked egg, then peanut. But never as whole nuts due to risk of choking. (For those with existing allergies these foods must still be avoided.)

★ Continue breastfeeding if possible through the first year and beyond.

★ Avoid food on skin and moisturisers containing almond or peanut oils. Allergenic foods should be introduced by mouth first.

★ For more information, see bit.ly/2SBpvJv

As for my son, he’s now six foot four and loves tuna and beans!