Parents hear a lot of mixed messages about how to prevent their children from developing food allergies. Do you start them young to boost their immune system? Or is it better to wait until they're more developed to give them foods such as peanuts? Well, new research seems to back up the former, which supports a previous study that suggested early exposure to the legumes dramatically cuts the chances that children will develop a peanut allergy.
The new research is a continuation of the Learning Early About Peanut Allergy (LEAP) study, which over a five-year period took children between four and 11 months of age who showed signs of a peanut allergy – such as already having severe eczema – and gave half of them peanut protein frequently until the age of five, while the other group were asked to completely avoid it. Both groups were then tested for their allergic reaction to peanuts. The researchers found that there was a more than 80 percent reduction in peanut allergy among those who were consuming the protein.
The researchers then decided to see if this apparent protection against the allergy persisted, even if the children stopped eating peanuts. They asked both groups from the original study to avoid eating peanuts for a further 12 months, before once again testing both groups for allergic reactions. What they found was that even after a break of a year, the group of children who were fed the peanut protein up to the age of five retained this tolerance to the legume, with 74 percent remaining allergy-free.
“[The research] clearly demonstrates that the majority of infants did in fact remain protected and that the protection was long-lasting,” Professor Gideon Lack, lead author of the paper published in the New England Journal of Medicine, told BBC News. “I believe that this fear of food allergy has become a self-fulfilling prophecy, because the food is excluded from the diet and, as a result, the child fails to develop tolerance.”
There is a word of caution from Professor Lack, however, as he stresses that due to the controls and limitations of the study, it might not be wholly representative of what happens in the real world, as the long-term effects of ceasing to eat peanuts after early introduction are not known. The researchers plan on next extending the study, to see if the tolerance persists even when the children are randomly consuming the legumes.
However, parents should be careful: “These studies were performed by trained allergists under controlled conditions,” says Professor Barry Kay of Imperial College London. “There are a few questions still to be answered before new, general, advice can be given. For instance, what are the correct amounts of foods needed to induce tolerance, and what is the age where it is too late to induce tolerance? There are also issues around the preparation of foods to make them easier for parents to administer. So, don’t try this at home yet.”