Omega-3 fatty acids, which are abundant in fish and fish oil supplements, may be beneficial for lung health, according to large, multi-faceted study in healthy adults.
The research, published recently in the American Journal of Respiratory and Critical Care Medicine, provides the strongest evidence to date of this association.
It underscores the importance of including omega-3 fatty acids in the diet, especially given that many Americans do not meet current guidelines, 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 corresponding author Patricia A. Cassano from Cornell University in the US.
“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,” said Cassano said.
Past studies have suggested that omega-3 fatty acids may help, due largely to their established anti-inflammatory actions. However, robust studies of this association have been lacking, until now.
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 15,063 Americans from the NHLBI Pooled Cohorts Study — a large collection of studies that 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. They comprised a racially diverse group of adults, with an average age of 56 years, and 55 per cent were female.
The researchers followed participants for an average of seven years and up to 20 years.
The 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 analysed genetic data from a large study of European patients (over 5 lakh 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, the researchers said
In addition to fish and fish oil, 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, director of the National Heart, Lung, and Blood Institute (NHLBI) 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,” Kiley added.
