Omega-3 fats seem to have a protective effect on allergies in children.
One year olds whose mothers had ingested fish oil during pregnancy and breastfeeding had considerably fewer allergic reactions than children whose mothers did not take this supplement, according to a study from Linkoping University in Sweden.
The study, which started in 2005, comprised 145 pregnant mothers with families at heightened risk of developing allergy and asthma. From the 25th week of pregnancy through the third month of nursing, they were asked to take nine capsules of oil every day. Half of them were given fish oil with high levels of omega-3 fatty acids, and the other half were given a placebo in the form of soybean oil.
The study was doubly blind, that is, neither the participants nor the researchers knew who had received what.
It turned out that the "fish-oil children" had fewer than half as many reactions to eggs at the age of one year as the placebo group did. This is an important discovery, since allergic reactions to eggs early in life are strongly correlated with the later development of allergic disorders like eczema and asthma.
All of the children are now two years old and have undergone a clinical examination regarding eczema, been scratch-tested for eggs, milk, and cats, and left a blood sample.
The idea that the difference is truly an effect of the omega-3 fats is supported by an immunological study of the mothers' blood. The women who were given fish oil had less prostaglandin E2 in their blood than the others. This is a substance that triggers allergic immune responses, and it is known that it is depressed when the concentration of omega-3 increases.
"We have been able to show that omega-3 influences the mother's immunological profile in a less inflammatory direction.
Theoretically this can also affect the child's immune system, which is supported by the results of the scratch-tests," says the immune biologist Malin Fageras Bottcher, who led the study together in collaboration with the child allergist Karel Duchen.