Omega-3 Supplements Could Help Prevent Childhood Asthma

01/02/2017 07:52 pm ET Updated Jan 05, 2017

Simple preventative supplementation during a mother’s pregnancy with omega-3 fatty acid can reduce, by almost one-third, the child’s risk of developing asthma. Currently, one in five young children suffers from asthma or a related wheezing disorder.

Omega-3s are accepted as essential regulators of human immune responses. Their anti-inflammatory properties are what make them so useful in preventing cardiovascular disease. Omega-3 supplementation has also shown efficacy in the treatment of depression.

This additional therapeutic benefit was demonstrated by the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) and the University of Waterloo. The new study is published in the New England Journal of Medicine. The University of Waterloo developed the rapid analytical techniques needed to measure levels of EPA and DHA in blood and has one of the few laboratories in the world equipped to run the tests.

Researchers in this study found that women who took 2.4 grams of an omega-3 supplements, known as long-chain fatty acids, during their third trimester reduced their children’s risk of asthma by 31 percent. Long-chain omega-3 fatty acids, which include eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are found in cold water fish.

Americans consume approximately 1.6 grams of omega-3 fatty acids daily, but most of this comes from another omega-3 fatty acid, alpha Linolenic acid (ALA), while only 0.1-0.2 grams comes from EPA and DHA. The American Heart Association recommends that people eat oily fish twice a week, but therapeutic levels of omega-3 are difficult to reach. For instance, three ounces of cooked salmon has between 500 and 1,500 milligrams of omega-3. Similar servings of tuna, grouper, or halibut could yield as little as 200 milligrams. The calorie and fat content of enough fish to reach 2,400 milligrams could be prohibitive. Vegetarians and vegans obviously need to seek supplementation.

The comprehensive health benefits of omega-3 fatty acids make it clear that finding a way to include them in the diet is important to achieving and maintaining good health. “We’ve long suspected there was a link between the anti-inflammatory properties of long-chain omega-3 fats, the low intakes of omega-3 in Western diets and the rising rates of childhood asthma,” said Professor Hans Bisgaard of COPSAC at the Copenhagen University Hospital. “This study proves that they are definitively and significantly related.”

Women who had low blood levels of EPA and DHA at the beginning of the study benefitted the most from the supplements, reducing their children’s relative risk of developing asthma by 54 per cent. The number of Canada and American women with low EPA and DHA levels is greater than in Denmark. Consequently, an even greater reduction in risk among North Americans would be expected.

“Identifying these women and providing them with supplements should be considered a front-line defense to reduce and prevent childhood asthma,” said Professor Ken Stark, Canada Research Chair in Nutritional Lipidomics and professor in the Faculty of Applied Health Sciences at Waterloo.

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