New evidence from a large, comprehensive study in healthy individuals financed by the National Institutes of Health suggests that omega-3 fatty acids are promising for sustaining lung health.

The study presents the most convincing evidence of this link to date and highlights the significance of consuming omega-3 fatty acids, particularly in light of the fact that many Americans fall short of the recommended amounts.

“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 corresponding author Patricia A. Cassano, PhD, director of the Division of Nutritional Sciences at Cornell University in Ithaca, New York.

“This study adds to growing evidence that omega-3 fatty acids, which are part of a healthy diet, may also be important for lung health."

Whether nutritional therapies could aid in the fight against lung illness has recently gained more attention. Because of their well-documented anti-inflammatory effects, omega-3 fatty acids have been linked to promising results in earlier studies.

However, until recently, there haven't been any reliable investigations of this link. To learn more, 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 15,063 Americans from the NHLBI Pooled Cohorts Study helps researchers to study determinants of personalised risk for chronic lung disease.

The participants studied were generally healthy when the study began, and the majority had no evidence of chronic lung disease.

The researchers followed participants for an average of seven years and up to 20 years. 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 see foods. DHA is also available as a dietary supplement.

In the second part, the researchers analysed genetic data from a large study of European patients (over 500,000 participants) from the UK Biobank.

They studied certain genetic markers in the blood as an indirect measure, or proxy, 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, 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 or COPD  including heavy smokers to determine 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,” said study first author Bonnie K. Patchen, Ph.D., a nutritionist and member of Cassano’s research team at Cornell.

“In the future, this could translate into individualised dietary recommendations for people at high risk for chronic lung disease.”

For now, the researchers point out that the US Department of Agriculture’s Dietary Guidelines for Americans recommends that people eat at least two servings of seafood per week, which most Americans fall far short of.

In addition, other sources of omega-3 fatty acids include nuts and seeds, plant oils, and fortified foods.

“This large population-based study suggests that nutrients with anti-inflammatory properties may help to maintain lung health,” said James P Kiley, PhD, director of the NHLBI’s Division of Lung Diseases.

“More research is needed since these findings raise interesting questions for future prospective studies about the link between omega-3 fatty acids and lung function.”