Peanut allergy is increasing in children although the cause is unclear. The use of peanuts and peanut oil in the British diet has increased rapidly over the last few years. (Although crude peanut oil can contain peanut allergens, refined peanut oil is a neutralised bleached deodorised product which is considered safe in peanut allergic individuals). Peanut allergy affects up to 1 in 50 children in the UK.

In the UK, research has been ongoing for a while now to see if there is an association between a mother eating peanuts when pregnant or breastfeeding and the incidence of peanut allergy in later life. In 1998 the UK Government made a recommendation that if you or your child's father or any of your existing children suffer from asthma, eczema, hay fever or allergies it would be sensible to avoid peanuts and products containing them during your pregnancy and while breast feeding.

There is now a need to review this advice in the light of scientific studies that have been published since 1998, and to consider whether the Government advice is still appropriate. Some recent studies have given rise to the suggestion that early oral exposure to allergens such as peanuts may in fact be protective against allergy, and some have suggested that the current avoidance advice may have contributed to a rise in peanut allergy and/or sensitisation in recent years. It is thought that there is a critical window of time during early infant life when the immune system is developing which may be a key time for the development of allergies, but it is not clear how the route, timing and dose of exposure to food allergens during this period might influence whether the child develops an allergy or not.

One theory that has emerged recently is that high levels of consumption of food allergens at an early age may in fact prevent the development of food allergy by inducing tolerance, but there is a need to gain more definitive evidence to be able to support or reject this theory. To achieve this, a major clinical intervention study is being funded by the US National Institute of Health, called the Learning Early About Peanuts study - in which young children at high risk of developing peanut allergy are being recruited and randomised to either eat peanut at high levels from an early age or to exclude peanut from their diet. A series of diagnostic tests will be done over 5 years to monitor whether the children develop peanut allergy or not.

The need to reconsider the current Government advice (based on the 1998 recommendations), was a specific recommendation in the recent report of the House of Lords Science and Technology Select Committee on Allergy, published in September 2007. This work will be undertaken by the Food Standards Agency.