Low omega-3 index just as powerful predicting early death as smoking

A low omega-3 index is just as powerful in predicting early death as smoking, according to a new research paper published in the American Journal of Clinical Nutrition.

The study included data pulled and analyzed from the Framingham Heart Study. The study provided insights into cardiovascular disease (CVD) risk factors and led to the development of the Framingham Risk Score based on eight baseline standard risk factors, including age, sex, smoking, hypertension treatment, diabetes status, systolic blood pressure, total cholesterol (TC), and HDL cholesterol.

CVD is still the leading cause of death globally, and risk can be reduced by changing behavioral factors such as unhealthy diet, physical inactivity, and use of tobacco and alcohol. Therefore, researchers in this study say biomarkers integrating lifestyle choices might help identify individuals at risk and be useful to assess treatment approaches, prevent morbidity, and delay death.

Among the diet-based biomarkers are fatty acids (FAs), whether measured in plasma or red blood cell (RBC) membranes. The FAs most clearly associated with reduced risk for CVD and for total mortality (i.e., death from any cause) are the omega-3 FAs, EPA and DHA, which are typically found in fish like salmon and herring, as well as omega-3 supplements like fish and algal oil.

In a 2018 report that included 2500 participants in the Framingham Offspring Cohort followed for a median of 7.3 years, the baseline RBC EPA + DHA content [the omega-3 index (O3I)] was significantly and inversely associated with risk for death from all causes. Individuals with the highest omega-3 index were 33 percent less likely to succumb during the follow-up years compared with those with the lowest index.

The Omega-3 Index measures the amount of EPA and DHA in red blood cell membranes and is a marker of omega-3 status. An optimal omega-3 index is 8 percent or higher, an intermediate omega-3 index is between 4 percent and 8 percent, and a low omega-3 I=index is 4 percent and below. Most Americans have an omega-3 index below 4 percent, which puts them a significantly higher risk of early death, the researchers said.

According to the researchers, the finding that any FA-based metric would have predictive power like that of the well-established standard risk factors was unexpected, and it suggests that RBC FAs, via imperfectly understood mechanisms, somehow reflects an in vivo milieu that consolidates into one measure the impact on the body of all these standard risk factors.