A new research paper published in the American Journal of Clinical Nutrition found that, among 2,500 participants of the Framingham Study (one of the longest-running clinical studies in the world), having low blood concentrations of Omega-3 fatty acids was just as strong a predictor of early death as smoking status.
 
The Framingham Heart Study provided unique insights into cardiovascular disease risk factors, and has led to the development of the Framingham Risk Score, based on 8 baseline standard risk factors – age, sex, smoking, hypertension treatment, diabetes status, systolic blood pressure, total cholesterol, and HDL cholesterol.
 
CVD is still the leading cause of death globally, the authors of the study report, and risk is influenced by having an overall unhealthy diet, physical inactivity, and the use of tobacco and alcohol. Therefore, researchers in this study sought to quantify different biomarkers of lifestyle choices that might help identify individuals at risk, and assess treatment approaches, prevent morbidity, and delay death.
 
Among diet-based biomarkers were fatty acids, measured in either plasma or red blood cell membranes. The fatty acids with the strongest influence on CVD risk were the omega-3s EPA and DHA, which are found in fish, as well as supplements like fish and algal oil.
 
In the study, which had a follow-up period of 7.3 years in participants between the ages of 66 and 73, the baseline omega-3 index was significantly and inversely associated with all-cause mortality – individuals who had the highest omega-3 index were 33% less likely to die during the follow-up years compared with those who had the lowest omega-3 index. These results are similar to those seen in the Women’s Health Initiative Memory Study, the Heart and Soul Study, and the Ludwigshafen Risk and Cardiovascular Health Study.
 
The Omega-3 index measures the amount of EPA and DHA in red blood cell membranes, and is a marker of omega-3 status. The optimal Omega-3 index, according to the authors of the study, is 8% or higher – an intermediate Index sits between 4% and 8%. A low Omega-3 Index is considered to be 4% and below. Most Americans, the authors report, have an Omega-3 Index below 4%, significantly increasing their risk of early death.
 
“It is interesting to note that in Japan, where the mean Omega-3 Index is greater than 8%, the expected life span is around five years longer than it is in the United States, where the mean Omega-3 Index is about 5%. Hence, in practice, dietary choices that change the Omega-3 Index may prolong life,” Michael McBurney, PhD, FCNS-SCN, lead researcher in this study, said. “In the final combined model, smoking and the Omega-3 Index seem to be the most easily modified risk factors. Being a current smoker [at age 65] is predicted to subtract more than four years of life [compared with not smoking], a life-shortening equivalent to having a low vs. a high Omega-3 index.”
 
“The information carried in the concentrations of four red blood cell fatty acids was as useful as that carried in lipid levels, blood pressure, smoking, and diabetic status with regard to predicting total mortality,” Dr. Bill Harris, co-inventor of the Omega-3 Index Test and a co-author on the study, said. “This speaks to the power of the Omega-3 Index as a risk factor and should be considered just as important as the other established risk factors, and maybe even more so.”
 
The study was supported in part by the nonprofit Institute for the Advancement of Food and Nutrition Sciences (IAFNS) through an International Life Sciences Institute North America Lipid Committee grant.