Omega-3 polyunsaturated fatty acids modify the inverse association between systemic inflammation and cardiovascular fitness.

BACKGROUND AND OBJECTIVE

Exercise increases quality of life and lowers all-cause mortality, likely by preventing cardiovascular disease. Although the beneficial effects of exercise are linked with reductions in chronic inflammation, individual responses vary and factors that contribute to the anti-inflammatory effects of cardiovascular fitness remain largely undefined. We sought to investigate the role of fatty acids in the inverse relationship between inflammation and cardiovascular fitness.

APPROACH AND RESULTS

In this cross-sectional study using data from 435 participants in NHANES and linear regression models with CRP as the outcome, we observed significant negative interactions between VOmax and omega-3 polyunsaturated fatty acids (PUFAs) but not saturated, monounsaturated, or omega-6 PUFAs. When stratified by omega-3 PUFA tertiles, participants in the medium tertile, but not low tertile, show an enhanced negative association between VOmax and CRP, with a -32.0% difference (95% CI: -44.95, -15.9%) per 10 mL/kg/min of VOmax. Exploratory factor analysis identified five unique dietary fatty acid (FA) profiles. The FA profile consisting predominantly of omega-3 PUFA had the strongest negative association for VOmax and CRP, with a -28.2% difference in CRP (95% CI: -43.4, -8.9) per 10 mL/kg/min of VOmax. We also found that alpha-linolenic acid (ALA) and docosahexaenoic acid (DHA) enhanced the negative association between VOmax and CRP, suggesting that the anti-inflammatory response to VOmax capacity is associated with ALA and DHA levels. Males, Whites, and individuals with lower BMI were more sensitive to the effects of omega-3 PUFAs, while having high SFA levels attenuated the benefit.

CONCLUSIONS

This study suggests that omega-3 PUFAs are effect modifiers for VOmax and CRP and that the anti-inflammatory benefits of increasing cardiovascular fitness are associated with omega-3 PUFAs.