In the past 15 – 20 years, the number of peanut allergic children has increased dramatically. From 0.5% to 1.0% in England and an increase from 0.4% to 0.8% in the United States. Peanuts and tree nuts account for most life-threatening or fatal food reactions.
Authorities have recommended in the past that mothers avoid eating peanuts during pregnancy and breast-feeding, and that peanut products be withheld for the first few years of life, but this was done with little scientific basis. It is completely unclear if mothers followed the advice.
Some scientists now say that early eating of peanuts decreases the development of peanut allergy but that environmental exposure without consumption increases the risk.
Israeli children commonly consume peanuts in infancy because of the availability of spongy peanut snacks that dissolve easily in saliva. The prevalence of peanut allergy in children in Israel is 0.17% but Jewish schoolchildren in the United Kingdom had more than 10 times higher rates of peanut allergy at 1.85%.
Peanut is introduced earlier and is eaten more frequently in Israel than in the United Kingdom. Boiling and roasting, different methods of preparation can change allergenicity – the tendency to cause allergy.
Most peanut allergies present on first exposure to peanut and this raises the question if environmental sensitization by low-dose skin exposure increases risk. There is a difference in allergic children’s’ mothers’ peanut consumption during pregnancy and lactation. There is a relationship between household peanut exposure and the development of peanut allergy.
Evidence does not support a strong relationship between the timing of introducing complementary foods and the development of allergy. The later introduction of solids has no protective effect on asthma, allergy, or atopic dermatitis (eczema), regardless of family history of allergies
There is not enough evidence to recommend restricting maternal diet during either pregnancy or lactation or in infants after 4 to 6 months of age. The recommendations apply to all allergenic foods, including peanut.
So why not give peanuts early in life on purpose? There is not sufficient evidence to suggest that early consumption of peanuts has a protective effect or that environmental exposure to peanut–as distinguished from maternal consumption–puts children at risk.