Emily P. Brigham
A recent study, named AsthmaDIET, found evidence that children with a diet higher in omega-3 fatty acids had fewer asthma symptoms caused by indoor air pollution, whereas children with diets higher in omega-6 fatty acids experienced more severe asthma symptoms.
“Dietary intake is another exposure that is increasingly recognized as important in lung health,” Emily P. Brigham, MD, MHS, assistant professor of medicine at Johns Hopkins University School of Medicine, told Infectious Diseases in Children. “Omega-3 fatty acids are the precursors of molecules known as ‘pro-resolving mediators,’ which help to promote the resolution of inflammation in the body and can be found in the lung. Omega-6 fatty acids give rise to a more complex balance of anti- and pro-inflammatory compounds but are notably the source of leukotrienes, a key molecule involved in asthma pathogenesis and morbidity.”
The environmental cohort study followed 149 children with asthma aged 5 to 12 years in Baltimore. Participants were diagnosed with asthma or used reliever medication in the 6 months leading up to the study, had no food allergies and were not taking antibiotics at the start of the study.
Children underwent week-long assessments for indoor particle matter (PM) concentrations, dietary intake, daytime and nighttime asthma symptoms, albuterol use and phlebotomy at baseline and again at 3 and 6 months. Impactors placed in each child’s home during the assessments measured two types of indoor particle pollution known to trigger asthma symptoms in children — PM2.5 and PM10.
Based on National Asthma Education and Prevention guidelines, 34% of participants had mild asthma, 33% had moderate asthma and 33% had severe asthma.
For each gram of omega-6 intake, children were 29% more likely to have severe asthma, researchers said. Each additional gram of omega-6 was associated with higher odds of experiencing symptoms associated with PM2.5 and PM10 particles. Moreover, diets higher in omega-6 were associated with higher percentages of neutrophils, a type of blood cell linked with inflammation caused by air pollution.
Researchers found that for each 0.1-g increase in omega-3 fatty acid intake, participants were 3% to 4% less likely to have daytime asthma symptoms in response to both sizes of indoor air pollutants.
“We’re not at the point where we can change recommendations on diet specifically for children with asthma. However, because there is mounting evidence that diet is important in lung health, following dietary recommendations from the American Dietary Association for a well-balanced, healthy diet is always a great idea,” Brigham said. “Avoiding processed, fried and fast foods is a good practice. And we shouldn’t wait to increase access to healthy foods to all children and adults, given the established effects on obesity, diabetes and cardiovascular disease.”– by Erin Michael
Disclosures: Brigham and the study were funded by the NIH. The study was cosponsored by the Environmental Protection Agency.