The development in children of allergies to certain foods – particularly peanuts – has been shown to be affected by the age of the child at the time those foods are first introduced into the child’s diet.
Familiarity with the food seems to prevent bad reactions in children at risk of developing food allergies and also protect the child from allergic reaction beyond the period during which they eat those particular foods. A technique has been used to introduce peanuts to children who might have allergies, but the exact timing of the foods introduction, whether it could be applied to foods other than peanuts, and whether it might be beneficial to a broader range of children rather than just those thought to be at risk were all unclear. Janet Peacock of the Unit for Medical Statistics has been involved in a study, led by Professor Gideon Lack of King’s College London, that considered these questions.
Breast-fed infants were given six types of foods that are known to cause a reaction – peanuts, cooked egg, wheat, sesame, whitefish and cow’s milk – and their development of allergies was then monitored. For children between the ages of one and three, some slightly ambiguous results were found with no difference in the development of allergies between those who were and were not given the foods. However, a difference was found in a smaller subset of infants who adhered strictly to the rules of the study. Looking at this latter group, the foodstuffs that had this affect seemed to be peanuts and egg.
The study has shown that this kind of feeding regime has a beneficial effect when applied to all children, not just those at risk of developing allergies, and It also may affect previous advice recommending that children be fed exclusively on breastmilk for the first six months of life. Having said that, the ambiguity in the results originated in the practical difficulties of getting babies to adhere strictly to the diet, so at best it is only possible to say that the benefits only occur if there is strict adherence to a feeding regime, which, may not be a practical solution to the problem of food allergies. It should also be made clear that the babies in this study were fed peanut derived products, and that no baby should be fed whole, or even broken up peanuts as there is a risk of choking.
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