The relationship of fish oil supplements and plasma fatty acids with lung function decline

Fish oil supplements and plasma fatty acid levels were reported to be associated with lung function. We aimed to investigate the association of fish oil supplements and plasma fatty acids with lung function.

We included 248,133 participants with complete data on relative index of plasma fatty acids from the UK Biobank. Linear regression models were used to investigate associations of fish oil supplements and plasma fatty acids with pulmonary function. Mediation analysis was performed to identify the potential mediating role of plasma fatty acid. All analyses were multivariable-adjusted.

Higher lung function was observed in fish oil users (14.59 ml for FEV1 and 17.92 ml for FVC). We found that each 1-unit increment of plasma PUFA, omega-3, omega-6, DHA, LA, and PUFA/MUFA were positively associated with lung function (6.74 ml, 6.15 ml, 5.81 ml, 22.23 ml, 7.44 ml, and 66.67 ml for FEV1, respectively; 9.04 ml, 3.39 ml 8.63 ml, 25.51 ml, 9.53 ml, and 93.02 ml for FVC, respectively), while SFA and MUFA were inversely associated with lung function (-8.74 ml and -8.19 ml for FEV1, respectively; -10.44 ml and -11.83 ml for FVC, respectively). Omega-6/omega-3 only showed a negative association with FEV1 (-1.17 ml). Mediation analysis suggested that plasma fatty acids partly mediated the associations between fish oil supplements intake and lung function, mainly DHA (34.70% and 31.50% for FEV1 and FVC, respectively).

We provided evidence that fish oil supplements and plasma fatty acids were both associated with lung function parameters, and the positive association between fish oil intake and lung function was mainly mediated by DHA.