The country's Department of Health advises that pregnant women with a family history of allergies may with to avoid eating peanuts, and not feed them to their children until they are at least three years old. This advice dates from 1998, when the Food Standards Agency's Committee on Toxicology (COT) last reviewed the evidence.
A report from the Lords' Select Committee on Science and Technology on allergy noted that the most dramatic increase in food allergy prevalence in recent years has been seen for peanut allergy. The Isle of Wight Birth Cohort Study reported in 2002 that peanut sensitisation had "increased three-fold" in children born between 1994 and 1996, compared to those born in 1989."
However the Committee drew on evidence from a number of experts, who cited studies indicating that exposing a child's immune system to peanut allergen at an early age could actually result in tolerance.
In particular, they said that in Israel, where the incidence of peanut allergy is lower than in the UK, peanuts are commonly used in infants' weaning foods.
This means that the present advice could actually be contributing to the problem. If this is the case, this means not only that consumer choice is being unnecessarily restricted, but industry, too, could be shouldering restrictions to use of peanuts in products without due cause.
"We are very concerned that Department of Health dietary advice regarding peanut consumption for pregnant women and infants is based upon evidence that was reported nine years ago… We recommend that this advice should be withdrawn immediately, pending a comprehensive review…" said the Lords' committee, which is chaired by Baroness Finaly of Llandaff.
The matter is due to be researched further by Professor Gideon Lack, head of paediatric allergy at Imperial College, London, who has received funding from the Immune Tolerance Network for in interventional study involving 480 infants aged between four and 11 months. Half of the children will receive peanut products regularly and the other half will avoid them. They will then receive allergy testing, dietary counseling, and physical examinations until the age of five years.
"It is hoped that analysis of the proportion of children in each group which develops peanut allergy, will help to determine whether avoidance or consumption reduces the risk of developing the allergy," said the report.
As for the efficacy of current advice on peanuts, the Food Standards Agency recently supported two studies. One of these, published in April (Dean et al, Journal of Human Nutrition and Dietetics 20, 2007, pp95-99) said that mothers often misunderstand the advice, and that those communicating it had "not fully explained who it is targeted at.
Moreover, it concluded that "the target population did not necessarily take up this advice", and that some women who did not have a family history of atopy - at which the advice was not aimed - were avoiding peanuts.
The FSA says it has already started reviewing evidence, which will be presented to the COT.
The COT will consider this at an open meeting, and its conclusions will be taken on board by the government.
The FSA says it has already begun the process of identifying and systematically reviewing the evidence, and a paper will be taken to the COT as soon as this review is complete. The COT will then consider this evidence at an open committee meeting and will issue a statement. After that, the Government will reconsider its advice in the light of the views of the COT.
"Given the need to evaluate fully and carefully all the relevant scientific evidence, this process is likely to take six to 12 months," said the Lords' report.
A spokesperson fro Asthma UK said that consumers should continue to follow government advice until such time as it is updated.