Cardiovascular disease (CVD) is still the leading cause of death globally. Many factors contribute to its development, but unhealthy lifestyles, particularly diet, inactivity, and smoking, are key risk factors. 

According to research, a healthy diet consisting of wholegrains, vegetables, fruits, nuts, seeds, and protein-rich foods such as legumes and seafood provides many anti-inflammatory nutrients such as essential omega-3 fatty acids that lower CVD risk.  

New evidence has expanded omega-3 FA benefits by showing that high blood levels of omega-3 FAs may increase life expectancy by almost five years. Smoking, however, reduces life expectancy by an equal amount. 

The study, “Using an erythrocyte fatty acid fingerprint to predict risk of all-cause mortality: the Framingham Offspring Cohort,” was published in The American Journal of Clinical Nutrition.

Fatty acids (FA) regulate many processes in the body and are crucial for signalling and protein production. They are present in many tissues, including plasma, adipose (fat) tissues and red blood cell membranes. 

The types of FA present in fat tissue reflect long-term dietary habits, while those in red blood cells reflect shorter-term (weeks) dietary habits and are predictors of CVD risk. Omega-3 FAs, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are associated with a lower CVD risk, while trans and omega-6 FAs confer higher risks. 

However, many other types of FAs exist that may contribute to CVD risk. In addition to known risk factors, understanding how FA patterns rather than individual FAs affect CVD risk could improve the predictability of CVD risk. A team of researchers now sought to investigate whether FA patterns combined with known risk factors could accurately predict CVD risk.

A total of 2240 participants who attended the 8^th examination cycle of the Framingham Offspring Cohort study were included in the study. The mean age of the participants was 65 years, 9.3% were current smokers, 43% were undergoing treatment for hypertension, and 12.8% had prevalent diabetes. Participants were followed for 11 years.  

In addition to omega-3 FAs, three other FAs – myristic acid, palmitoleic acid, and behenic acid – accurately predicted CVD risk. This finding was significant because omega-3 comprise only 5% of the total FAs in red blood cells, while myristic, palmitoleic, and behenic acids comprise less than 0.4%.

“It is remarkable that FAs present in such low percentages could carry such predictive power,” the researchers wrote. 

High levels of omega-3, myristic and behenic acids were associated with a lower CVD risk, while high palmitoleic acid levels were associated with an increased CVD risk. 

Moreover, people with the highest blood omega-3 FA levels had a five-year longer lifespan than those with lower intake. However, having diabetes or being a current smoker shortened lifespan by 3.9 and 4.7 years, respectively. 

Besides omega-3 FA, myristic and behenic acid were associated with a longer life expectancy, which was somewhat unexpected as they are saturated FAs – a group of FAs often linked to high CVD risk. 

“This reaffirms what we have been seeing lately; not all saturated fatty acids are necessarily bad,” Alex Sala-Vila, PhD, postdoctoral researcher, and lead author of the study, said. “Indeed, their levels in the blood cannot be modified by diet, as happens with omega-3 fatty acids,” he added. 

These findings may promote FA-blood profiling tests as tools to personalise dietary recommendations and encourage people to adopt healthier diets. “What we have found is not insignificant. It reinforces the idea that small changes in diet in the right direction can have a much more powerful effect than we think, and it is never too late or too early to make these changes,” Sala-Vila added.

Study limitations the researchers noted included applying risk factors for younger people to estimate the death rate in an older population, and including people with type 1 diabetes in the analysis. 

Nevertheless, “having higher levels of omega fatty acids in the blood, as a result of regularly including oily fish in the diet, increases life expectancy by almost five years,” Sala-Vila said.