Omega-3s seen to enhance heart rate and rhythm during rest and exercise; results add to omega-3s cardiac benefits
by Craig Weatherby
Older men, take heart. The positive results of a small but well-designed new study confirm and expand the promise of omega-3s for heart health.
We know that men who have high heart rates at rest suffer a greater risk of heart attack, and we know that the marine omega-3s in fish oil help moderate heart rhythms in ways that help prevent heart attacks.
But this new study was the first to test the effects of supplemental omega-3s on three things in active male heart attack survivors: heart rate, the variability of heart rates, and heart rate recovery (reduction) after exercise. Conducted by researchers at the Mid America Heart Institute and the University of Missouri, it was published in The American Journal of Cardiology (O'Keefe JH Jr, 2006).
The well-controlled Missouri trial involved 18 white men—aged 68 on average—who had suffered a heart attack three months to five years before the study began. The researchers employed a rigorous methodology designed to eliminate as much error as possible (randomized, double-blind, placebo-controlled, crossover).
Half of the men took three fish oil capsules per day, each containing 75 mg of EPA and 195 mg of DHA—the two vital omega-3s found in fish oil and human bodies—for a total daily omega-3 intake of 810 mg. The other half took placebo capsules that contained a 50/50 blend of olive and corn oil.
After taking fish oil capsules for four months, the men in the omega-3 group enjoyed significant improvements in three areas:
- Reduced resting heart rate
- Enhanced heart rate variability in the critical “high-frequency band”
- A rapid, healthy, 19 percent decrease in heart rate within one minute after ending exercise
As in one prior study (Mehta JL 1998)—but unlike other high-dose omega-3 supplementation trials—the Missouri team found no changes in blood pressure, signs of inflammation, or blood vessel elasticity among the omega-3 group.
All in all, this new study reinforces the idea that fish-derived “marine” omega-3s can help keep heart attack survivors alive. And, at least in part, it’s a matter of keeping the heart-rhythm right.
Were this Dick Clark’s American Bandstand, and “The Omega-3s” a new rock band, the kids would surely award them a very high score on account of that steady, life-saving beat.
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