Higher frequency of fish intake and healthy lifestyle behaviors may be associated with a lower platelet count in Japan: Implication for the anti-atherosclerotic effect of fish intake

Background: Habitual fish intake and healthier lifestyles are associated with a lower risk of atherosclerotic cardiovascular disease (ASCVD). Higher platelet counts (PLCs) are reportedly associated with higher ASCVD events. We aimed to investigate the association between fish intake and lifestyle with PLCs. Methods: We conducted a cross-sectional study in a cohort of 9329 participants (average age: 46.9 ± 12.9 years; 58.9% men) with no history of ASCVD registered at the Health Planning Center of Nihon University Hospital in 2019. Results: The average fish intake frequency was 2.15 ± 1.28 days/week. As fish intake frequency increased (0, 1, 2, 3, 4, 5, 6, and 7 days), PLC decreased significantly (p < 0.0001). Multivariable logistic regression analysis showed that higher fish intake frequency tended to be a determinant of lower PLC. Aerobic exercise habits and sleep duration were independent negative determinants of PLC. Cigarette smoking habits were a positive independent determinant of PLC. Furthermore, with increasing fish intake frequency, the proportion of participants with habitual aerobic exercise, non-smoking habits, and longer sleep duration increased (p < 0.0001 for all). Higher n-3 polyunsaturated fatty acid (n-3 PUFA), calculated based on data from the Japanese National Health and Nutrition Survey, intake was associated with a lower PLC. Conclusion: Higher fish intake and healthier lifestyle behaviors may be comprehensively associated with lower PLCs. The intake of N-3 PUFA with anti-inflammatory effects, rich in fish, may also be related to the lower PLC. This association may explain the preventive effects of fish intake on ASCVD risk.