Fish consumption is associated with lower heart rates.

BACKGROUND: Fish consumption decreases risk of sudden death. The goal of the present study was to assess the relationship between fish consumption and heart rate. METHODS AND
RESULTS: A cross-sectional analysis was conducted of 9758 men, age 50 to 59 years, without coronary heart disease (CHD) who were recruited in France and Belfast, Ireland, from 1991 to 1993. Heart rate and CHD risk factors were compared among 4 categories of fish consumption, as follows: (1) less than once per week (n=2662), (2) once per week (n=4576), (3) twice per week (n=1964), and (4) more than twice per week (n=556). Fatty acid profiles of erythrocyte phospholipids were determined in a random subsample of 407 subjects. In erythrocyte phospholipids, eicosapentaenoic acid (P<0.0005), docosahexaenoic acid (P<0.0001), and total n-3 fatty acid (P<0.0008) increased across the categories of fish intake. Triglycerides (P<0.0001), systolic blood pressure (P<0.006), and diastolic blood pressure (P<0.0001) were lower and HDL cholesterol levels (P<0.004) were higher in fish consumers than in nonconsumers. Similarly, heart rate decreased across the categories of fish intake (P<0.0001). After adjustment for age, center, education level, physical activity, smoking habit, alcohol consumption, body mass index, and antiarrhythmic medications, heart rate remained statistically lower among fish consumers than among nonconsumers (P for trend <0.0001). Docosahexaenoic acid content of erythrocyte phospholipids was inversely correlated with heart rate (P<0.03).
CONCLUSIONS: Fish consumption is associated with decreased heart rate in men. Because heart rate is positively associated with risk of sudden death, this association may explain, at least in part, the lower risk of sudden death among fish consumers.