Omega-3 fatty acids , which are abundant in fish and fish oil supplements, show promise for maintaining lung health, according to new evidence from a large, multifaceted study in healthy adults supported by the National Institutes of Health. The study 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. Largely funded by the National Heart, Lung, and Blood Institute (NHLBI), part of the NIH, the study results were published in the American Journal of Respiratory and Critical Care Medicine .
"We know a lot about the role of diet in cancer and cardiovascular disease, but the role of diet in chronic lung disease is understudied," said corresponding author Patricia A. Cassano, Ph.D., 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."
There is increased interest in trying to understand whether nutritional interventions could contribute to lung disease prevention efforts . Previous studies have suggested that omega-3 fatty acids may help, due in large part to their established anti-inflammatory actions. However, solid studies of this association have been lacking, until now.
To find out more, researchers developed a two-part study that investigated the link between levels of omega-3 fatty acids in the blood and lung function over time. In the first part, researchers conducted a longitudinal observational study involving 15,063 Americans from the NHLBI Pooled Cohort Study, a large collection of NIH-funded studies that helps researchers study determinants of personalized disease risk. chronic pulmonary
The participants studied were generally healthy when the study began and most had no evidence of chronic lung disease. They were a racially diverse group of adults, with an average age of 56, and 55% were women. 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 decline in lung function. The researchers saw the strongest associations for docosahexaenoic acid (DHA), an omega-3 fatty acid 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, or proxy, of 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 to 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 lung function decline 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 the treatment of lung diseases," said the study’s first author, Bonnie K. Patchen, Ph.D., a nutritionist and member of the Cassano’s research at Cornell. "In the future, this could translate into individualized dietary recommendations for people at high risk of chronic lung disease."
For now, researchers point out that the U.S. Department of Agriculture’s Dietary Guidelines for Americans recommends that people eat at least two servings of fish per week , which most Americans fall short of. In addition to fish and fish oil, other sources of omega-3 fatty acids include nuts and seeds, vegetable oils, and fortified foods.
"This large population-based study suggests that nutrients with anti-inflammatory properties may help maintain lung health," said James P. Kiley, Ph.D., director of the Division of Lung Diseases at the NHLBI. "More research is needed, as these findings raise interesting questions for future prospective studies on the link between omega-3 fatty acids and lung function."
This study was supported by NHLBI award R01HL149352 and National Institute of Diabetes and Digestive and Kidney Diseases award T32DK007158. The NHLBI Pooled Cohort Study was supported by NIH/NHLBI awards R21HL121457, R21HL129924, and K23HL130627. For full details on funding information, please see the article published in the journal.
