An Update on Omega-3 Polyunsaturated Fatty Acids and Cardiovascular Health

Abstract

Interest in the potential cardiovascular (CV) benefits of omega-3 polyunsaturated fatty acids (Ω-3) began in the 1940s and was amplified by a subsequent landmark trial showing reduced CV disease (CVD) risk following acute myocardial infarction. Since that time, however, much controversy has circulated due to discordant results among several studies and even meta-analyses. Then, in 2018, three more large, randomized trials were released—these too with discordant findings regarding the overall benefits of Ω-3 therapy. Interestingly, the trial that used a higher dose (4 g/day highly purified eicosapentaenoic acid (EPA)) found a remarkable, statistically significant reduction in CVD events. It was proposed that insufficient Ω-3 dosing (<1 g/day EPA and docosahexaenoic acid (DHA)), as well as patients aggressively treated with multiple other effective medical therapies, may explain the conflicting results of Ω-3 therapy in controlled trials. We have thus reviewed the current evidence regarding Ω-3 and CV health, put forth potential reasoning for discrepant results in the literature, highlighted critical concepts such as measuring blood levels of Ω-3 with a dedicated Ω-3 index and addressed current recommendations as suggested by health care professional societies and recent significant scientific data.

A daily dose of fish oil increased the omega‐3 index in older adults and reduced their heart rate during a walking activity: A pilot study

“…The strengths of the current study include the accurate determination of blood omega‐3 status and, in keeping with best practice for omega‐3 trials, participants with a high omega‐3 index at baseline were screened out of the study. The supplementation duration and the dose of fish oil used are consistent with recent recommendations for dosage with consideration to baseline omega‐3 status (Elagizi et al, 2021). The measurement of a number of physiological parameters including walking speed and heart rate variability simultaneously with the measurement of heart rate allowed the interpretation of the effects of fish oil to be focussed on a likely intrinsic physiological effect within the heart.…”

Intake of Fish and Marine n-3 Polyunsaturated Fatty Acids and Risk of Cardiovascular Disease Mortality: A Meta-Analysis of Prospective Cohort Studies

“…In this meta-analysis, we also found a negative association between the marine n-3 PUFA intake and the CVD mortality risk. In previous studies, the results were not consistent [ 65 ]. A randomized controlled trial (RCT) showed that n-3 PUFA supplementation (866 mg/d) for 3.5 years could reduce CVD mortality risk [ 66 ].…”

Emerging Role of Phospholipase-Derived Cleavage Products in Regulating Eosinophil Activity: Focus on Lysophospholipids, Polyunsaturated Fatty Acids and Eicosanoids

“…Both, EPA and DHA supplementation was discovered to increase membrane fluidity and lipid raft clustering leading to Other important PUFAs involved in inflammation and allergy are the ω-3 acids eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6) (Figure 2). The supplementation of these ω-3 acids with diet was previously associated with favorable outcomes in a variety of disease models [147][148][149][150][151]. Both, EPA and DHA supplementation was discovered to increase membrane fluidity and lipid raft clustering leading to decreased cell activation [152].…”