BOSTON — Omega-3 fish oil, derived from the tissues of especially oily fish, has been linked to a number of different health benefits, including improved cardiovascular health. Consequently, fish oil dietary supplements have become a popular method of ingestion for people looking to enjoy these benefits without actually eating fish multiple times per day. With this in mind, researchers at Harvard University conducted a new study on the subject of omega-3 fish oil supplements and found an association between daily ingestion and a reduced risk of heart attack and most cardiovascular diseases.
The team at Harvard performed a comprehensive meta-analysis of randomized clinical trials, and found that people who received a daily omega-3 fish oil supplement had a lower risk of heart attack, death from coronary heart disease, and death from cardiovascular disease compared to those who were given a placebo instead. However, fish oil supplements did not lower participants’ risk of suffering a stroke.
It seems quantity plays a significant role in this relationship as well; higher doses of fish oil were linked to an even greater reduction in cardiovascular risk.
“This meta-analysis provides the most up-to-date evidence regarding the effects of omega-3 supplementation on risk of multiple CVD outcomes. We found significant protective effects of daily omega-3 supplementation against most CVD outcome risks and the associations appeared to be in a dose-response manner,” said first author Yang Hu, a postdoctoral fellow in the Department of Nutrition at Harvard Chan School, in a university release.
Observational studies in the past have found a link between eating fish regularly and reduced heart disease risk, but previous randomized controlled trials had yielded inconsistent results. For instance, two studies published in 2018 did not provide clear evidence of fish oil’s cardiovascular benefits.
So, for this new study, the research team performed an updated meta-analysis consisting of three recent large-scale trials. In all, the analysis included over 120,000 adults from 13 randomized trials worldwide. The research team left no stone unturned when it came to collecting data; even the VITAL trial, the largest randomized trial of omega-3s ever, was incorporated into the meta-analysis.
Participants who ingested daily omega-3 fish oil supplements showed a lower risk of most cardiovascular diseases, besides stroke, compared to those who took a placebo. Statistically, the oil supplement group exhibited an 8% lower risk of heart attack or death brought on by coronary heart disease.
As noted before, this association was even more prominent when participants were given even higher doses of omega-3 supplementation. This suggests to the research team that omega-3 supplementation dosages above the usual amount (840 mg/day) used in most randomized clinical trials may provide even greater reductions in cardiovascular risk.
So, it may be possible that the scientific community has underestimated what omega-3 fish oil can do for one’s cardiovascular health in high doses. This is a potentially groundbreaking, and certainly a significant finding: millions of people experience cardiovascular disease events each year, and even relatively tiny reductions in risk may be enough to avoid hundreds of thousands of heart attacks and cardiovascular disease-related deaths.
“Although public health recommendations should focus on increasing fish consumption, having an overall heart-healthy diet, being physically active, and having other healthy lifestyle practices, this study suggests that omega-3 supplementation may have a role in appropriate patients,” comments senior author Dr. JoAnn Manson.
The study is published in the Journal of the American Heart Association.