There is significant evidence that omega-3 fatty acids have a beneficial effect on heart arrhythmias (irregular heart beat), which can lead to a decreased risk of death from cardiovascular disease. New analyses indicate that regular fish oil intake could correspond to as much as a 5% reduction in population-wide sudden deaths.
A meta-analysis published in the journal Circulation further confirms the association between omega-3 fatty acids and heart health. Researchers from the Harvard School of Public Health compiled statistical data from thirty studies published from 1996 to 2005. These studies involved nearly 1,700 individuals treated with fish oil or placebo for up to one year. The average combined dose of EPA and DHA was 3.5 grams/day for an average of 8 weeks.
The overall estimated change in heart rate of those treated with fish oil was 1.6 beats per minute. The reduction in heart rate was even greater in trials where the participants had higher baseline heart rates. In those studies, treatment with fish oil resulted in a decreased heart rate of 2.5 beats per minutes. There was no evidence of a dose-response effect, and heart rate was not significantly different between higher and lower doses compared with placebo.
Although the overall effect of fish oil on heart rate appears small, researchers estimate that on a population-wide basis this could correspond to as much as a 5% reduction in sudden death.