A study at a leading Swedish Univeristy has found a beneficial link between the intake of omega-3 fatty acids and the incidence of childhood allergies.

Allergies are considered to be aberrations of an otherwise healthy immune system. After exposure to a specific substance, occasionally the body with 'decide' that it is a threat, and from then on over-react everytime we are re-exposed to this particular substance, whether it be hair, mites or even dust. The prostaglandin E2 is a molecule involved with triggering this over-reaction.

In the past, it has been noted that more concentrated amounts of omega-3 fatty acids in the diet leads to less serum prostaglandin E2. It was theorised that this decrease could also affect the immune system of the fetus in a pregnant woman. To test this hypothesis, a group studied 145 pregnant mothers whose families had a heightened risk of developing an allergy and asthma. From the 25th week of pregnancy until the third month of nursing, half of the women were given nine capsules a day of fish oil high in omega-3 fatty acids; the other half were given a placebo of soybean oil.

At one year old, the children born to the mothers given the fish oil had had less than half as many reactions to eggs as the offspring of mothers given soybean oil. Allergies in early childhood are nearly always associated with the 'atopic' type - children who suffer from the combination of hayfever, eczema and asthma. The mothers that had been fed fish oil had - as expected - a lower level of prostaglandin E2 in their blood compared to the placebo group. This study is ongoing and plans to collect data on the development of any allergies in the children.