Blood levels of seafood and plant-based omega-3 fatty acids are associated with a lower risk of dying from heart attacks, according to a new epidemiological study published in June in JAMA Internal Medicine.
The study was led by Liana C. Del Gobbo, Ph.D., a postdoctoral research fellow in the division of cardiovascular medicine at Stanford University School of Medicine and senior author Dariush Mozaffarian, dean of the Friedman School of Nutrition Science and Policy at Tufts University in Boston.
Researchers from around the world joined together to form the Fatty acids and Outcomes Research Consortium or FORCE.
By pooling findings from diverse large studies that had measured blood or tissue levels of omega-3 fatty acids, they evaluated relationships with heart disease events over time.
Each study performed new standardized, individual-level analyses.
The findings were then centrally pooled in a meta-analysis.
A total of 19 studies were involved from 16 countries and including 45,637 participants.
Of these, 7,973 people developed a first heart attack over time, including 2,781 deaths and 7,157 nonfatal heart attacks.
Overall, both plant and seafood-based omega-3s were associated with about a 10% lower risk of fatal heart attacks per standard deviation.
People with the highest blood levels of omega-3s had about 25% lower risk of fatal heart attack, compared to people with the lowest levels.
In contrast, these fatty acids biomarkers were generally not associated with a risk of nonfatal heart attacks, suggesting a more specific mechanism for benefits of omega-3s related to death.
“For the leading cause of death in the world, lowering the risk by about 25 percent would be quite meaningful,” said Mozaffarian.
“At a time when some but not other trials of fish oil supplementation have shown benefits, there is uncertainty about cardiovascular effects of omega-3s.”
“Our results lend support to the importance of fish and omega-3 consumption as part of a healthy diet.”
Fish is the major food source of omega-3 fatty acids, including eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid.
According to the US Department of Agriculture’s National Nutrient Database, fatty fish such as salmon, trout, anchovies, sardines, and herring contain the highest amounts of omega-3 fatty acids; although all fish contain some levels.
Fish also provide specific proteins, vitamin D, selenium, and other minerals and elements.
Alpha-linolenic acid is the plant-based omega-3 fatty acid found in walnuts, flaxseed oil, and canola oil and some other seed and nuts and their oils.
