Omega-3 fatty acids, which are abundant in fish and fish oil supplements, appear promising for maintaining lung health, according to a Cornell-led study supported by the National Institutes of Health (NIH).

The large, multifaceted study in healthy adults provides the strongest evidence to date of this association and underscores the importance of including omega-3 fatty acids in the diet, especially given that many Americans do not meet current guidelines, the researchers said.

“We know a lot about the role of diet in cancer and cardiovascular diseases, but the role of diet in chronic lung disease is somewhat understudied,” said Patricia A. Cassano, the Alan D. Mathios Professor in the College of Human Ecology (CHE) and director of the Division of Nutritional Sciences, which is housed jointly in CHE and the College of Agriculture and Life Sciences. “This study adds to growing evidence that omega-3 fatty acids, which are part of a healthy diet, may be important for lung health, too.”

Cassano, who is jointly appointed at Weill Cornell Medicine, is the corresponding author of “Investigating Associations of Omega-3 Fatty Acids, Lung Function Decline, and Airway Obstruction,” published July 20 in the American Journal of Respiratory and Critical Care Medicine. The first author is Bonnie K. Patchen, Ph.D. ’22, a postdoctoral researcher and member of the Cassano Research Group. The research was funded by the NIH’s National Heart, Lung, and Blood Institute (NHLBI) and National Institute of Diabetes and Digestive and Kidney Diseases.

There is increased interest in trying to understand whether nutritional interventions could help prevent lung disease, according to the researchers. Past studies have suggested that omega-3 fatty acids may help, due largely to their established anti-inflammatory actions, but robust studies of this association have been lacking. To learn more, the researchers developed a two-part study investigating the link between omega-3 fatty acid levels in the blood and lung function over time.

In the first part, the researchers conducted a longitudinal, observational study involving more than 15,000 diverse Americans from the NHLBI Pooled Cohorts Study – a large collection of NIH-funded studies that helps researchers to study determinants of personalized risk for chronic lung disease. The longitudinal study showed that higher levels of omega-3 fatty acids in a person’s blood were associated with a reduced rate of lung function decline. The researchers observed the strongest associations for docosahexaenoic acid (DHA), an omega-3 fatty acid that is found at high levels in fatty fish such as salmon, tuna and sardines. DHA is also available as a dietary supplement.

In the second part, the researchers analyzed genetic data from a large study of European patients (more than 500,000 participants) from the UK Biobank. They studied certain genetic markers in the blood as an indirect measure for dietary omega-3 fatty acid levels to see how they correlated with lung health. The results showed that higher levels of omega-3 fatty acids – including DHA – were associated with better lung function.

One caveat of the current study is that it only included healthy adults. As part of this ongoing project led by Cassano and Dana Hancock, senior vice president at RTI International, a nonprofit research institute headquartered in North Carolina, the researchers are collaborating with the COPDGene Study to examine blood levels of omega-3 fatty acids in relation to the rate of decline in lung function among people with chronic obstructive pulmonary disease (COPD) – including heavy smokers – to see if the same beneficial associations are found.

“We’re starting to turn a corner in nutritional research and really moving toward precision nutrition for treating lung diseases,” Patchen said. “In the future, this could translate into individualized dietary recommendations for people at high risk for chronic lung disease.”

The U.S. Department of Agriculture’s “Dietary Guidelines for Americans” recommends that people eat at least two to three servings of fish per week, a goal most Americans don’t meet. In addition to fish and fish oil, other sources of omega-3 fatty acids include nuts and seeds, plant oils and fortified foods.

This article was adapted from a National Heart, Lung, and Blood Institute press release.