A large, multi-disciplinary research team supported by the National Institutes of Health developed a two-part study to investigate the link between omega-3 fatty acid levels in the blood and lung function over time. It triangulated respiratory health findings from a longitudinal, observational study involving 15,063 Americans from the National Heart, Lung, and Blood Institute (NHLBI) Pooled Cohorts Study and genetic data from a study of over 500,000 European patients from the UK Biobank.
“Our study provides the strongest evidence to date for a potential role of omega-3 fatty acids in preserving long-term lung health and underscores the importance of including omega-3 fatty acids in the diet, especially given that many Americans do not meet current guidelines,” Bonnie Patchen, PhD, first author on the study and researcher in the Division of Nutritional Sciences at Cornell University, told NutraIngredients-USA.
The research, published in the American Journal of Respiratory and Critical Care Medicine, was funded through NHLBI and National Institute of Diabetes and Digestive and Kidney Diseases grants.
More robust correlations
The review acknowledged previous findings of the relationship between lung function and the anti-inflammatory properties of omega-3 fatty acids but indicated a need for more robust correlations.
In the first part of the study, the research team examined findings from the NHLBI Pooled Cohorts study that comprised a racially diverse group of adults found to be generally healthy and without evidence of chronic lung disease at baseline (average age 56 years, 55% female). The research followed participants for an average of seven years and up to 20 years.
“Our longitudinal pooled individual participant data analysis in a large, diverse U.S. population-based sample found that higher levels of omega-3 fatty acids in circulation were associated with an attenuated rate of lung function decline, with the strongest associations seen for DHA, the most metabolically downstream omega-3 fatty acid,” the researchers wrote. “Higher DHA was also associated with decreased risk of incident airway obstruction.”
In the second part of the study, the team analyzed 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. Results, although not significant across all Mendelian Randomization (MR) methods, trended towards positive associations of genetically predicted downstream omega-3 fatty acids with lung function.
“Together, the findings from the longitudinal and MR studies support a protective effect of higher levels of metabolically downstream omega-3 fatty acids—most significantly DHA—on lung health,” the researchers concluded.
The review also identified associations of lack thereof between various omega-3 fatty acids and lung function decline across sex, smoking histories and self-reported race and ethnicity, detecting both qualitative and quantitative differences.
“We found that the positive associations of ALA, EPA, and DPA with lung function decline were driven by males, white participants, and/or those with a history of smoking, with little to no evidence for associations in females, non-white participants, and non-smokers,” the researchers wrote. “In contrast, the positive association of DHA with lung function decline was observed in both males and females; in Black, white and Hispanic participants; and in all smoking groups, with the largest magnitude associations in Black and Hispanic participants and former smokers.”
These patterns, they added, are consistent with reported differences in the efficiency of omega-3 fatty acid metabolism by sex, race and ethnicity, and smoking.
More research needed
James Kiley, PhD, director of the NHLBI’s Division of Lung Diseases commented that the study “suggests that nutrients with anti-inflammatory properties may help to maintain lung health” but that more research is needed to answer the interesting questions raised.
Patchen shared that an important next step in this ongoing project is determining whether the same associations are found among persons with compromised lung function such as those with chronic obstructive pulmonary disease (COPD) in collaboration with the COPDGene study.
“The influence of genetic factors on the relationship of omega-3 fatty acids and lung function decline is also of interest,” she added. “Research considering the interplay of nutrition and genetics could help inform precision nutrition initiatives to promote lung health throughout the lifespan.”
Source: American Journal of Respiratory and Critical Care Medicine
“Investigating associations of Omega-3, fatty acids, lung function decline, and airway obstruction”
Authors: Bonnie K. Patchen et al.