“This new study by Jawad and colleagues provides powerful evidence that omega-3 fatty acids are protective against the development of heart failure, which is one of the most common causes of hospitalization in the United States today,” said William Harris, PhD, senior investigator on the study and president of the Fatty Acid Research Institute (FARI).
The study, which analyzed data from nearly 272,000 adults in the ongoing UK Biobank prospective cohort study, brought together researchers from the Saint Luke’s Mid America Heart Institute, Fatty Acid Research Institute, University of Illinois-Chicago and Harvard T.H. Chan School of Public Health.
Omega-3s and heart health
Associations between omega-3 consumption and heart health are nothing new. Interest intensified in the 1970s when Danish researchers observed that the native Inuit populations of Greenland, who consumed a diet rich in oily fish, had a very low rate of heart disease compared to Danes on the mainland.
Over the last three decades, dozens of randomized controlled trials continue to examine omega-3 fatty acids as preventive measure for cardiovascular events.
Jawal and colleagues referred to a 2021 meta-analysis of 40 of these trials among over 135,000 patients without heart failure. Sponsored by the Global Organization for EPA and DHA Omega-3s (GOED), it found that omega-3 supplementation reduced risk of myocardial infarction by 13% and fatal myocardial infarction by 35%.
Another recent meta-analysis of close to 30,000 patients with coronary artery disease showed that omega-3 reduced risk of all-cause mortality by 10%, cardiovascular mortality by 18%, myocardial infarction by 23%, sudden cardiac death by 33% and hospitalization for heart failure or unstable angina by 25%.
This latest study, while observational in nature, reported that people with the highest plasma omega-3 fatty acid levels (top 20%) were 21% less likely to develop heart failure over the 13.7 years of follow-up compared to people with the lowest levels (bottom 20%).
In the 1,239 people with a heart failure diagnosis at enrollment, those in the top 20% of plasma omega-3 levels were 50% less likely to die from any cause during follow-up compared with those in the bottom 20%.
“These findings suggest that increasing plasma omega-3 levels, whether by diet or supplementation, could reduce both risk for development of heart failure and death in those with prevalent heart failure,” the researchers concluded.
Mapping global O3I levels
A 2024 update of the omega-3 world map led by the Fatty Acid Research Institute shows that most countries with data (only 25% of countries) have a low Omega-3 Index (O3I) in the range of 4% to 6%.
Despite less-than-optimal results across much of the globe, the revised review charted some improvements since publication of the first world mapping in 2016 using O3I (defined as the sum of EPA and DHA in percentage of total fatty acids in red blood cells ) as biomarker of omega-3 intake.
“Notable differences between the current and 2016 map were 1) USA, Canada, Italy, Turkey, UK, Ireland and Greece (moving from the very low to low category); 2) France, Spain and New Zealand (low to moderate); and 3) Finland and Iceland (moderate to desirable),” the researchers reported. “Countries such as Iran, Egypt, and India exhibited particularly poor O3I levels.”
An index of 8% is proposed as a healthy or optimal target for reducing risk of death from coronary heart disease, with the review suggesting that an average intake of EPA + DHA of about 1.4 g/day would be required to move from an O3I of 4% to 8%.
“The medical profession needs to take seriously the long-term potential of these simple nutrients to address one of our major health challenges,” Dr. Harris said.
Source: Mayo Clinic Proceedings
doi: 10.1016/j.mayocp.2024.08.007
“Association of Plasma Omega-3 Levels With Incident Heart Failure and Related Mortalities”
Authors: Mohammad Abdel Jawad MD et al.
