Seafood rich in omega-3 may promote healthy ageing, find researchers

Higher blood levels of omega 3 fatty acids found in seafood are associated with a higher likelihood of healthy ageing among older adults, finds a US study published by The British Medical Journal

Image source: Google
Image source: Google

In our increasingly ageing society, it is worth asking: what can we do to ensure that we don’t just live longer lives, but also healthier ones? New research suggests one possible answer -eat more seafood!

Seafood contains fatty acids that may help people age healthily.

A new study, led by Heidi Lai from the Friedman School of Nutrition Science and Policy at Tufts University in Boston, MA, investigates the link between high consumption of omega-3-rich seafood and healthy ageing.

Lai and colleagues define ‘healthy ageing’ as “meaningful lifespan without chronic diseases and with intact physical and mental function.”

As the researchers explain in their paper, the problem of healthy ageing is increasingly important. Populations are ageing rapidly across the globe and the rates of chronic disease along with them.

So, more and more research is looking into what constitutes healthy ageing and what we can do to achieve it. In this regard, the studies on the link between omega-3 fatty acids and age-related chronic disease have been somewhat inconsistent.

For instance, some studies referenced by Lai and colleagues have found an inverse relation between omega-3 consumption and cardiovascular disease. However, others have found that omega-3 intake correlates with a higher incidence of prostate cancer.

Other studies have yielded ‘mixed or inconclusive’ results when it comes to omega-3s and “cancer, diabetes, lung disease, severe chronic kidney disease, and cognitive and physical dysfunction”

So, the researchers set out to clarify this potentially significant role that dietary omega-3 fatty acids play in the aging process. The scientists published their findings in the journal The BMJ.

Studying omega-3s and healthy ageing

The team examined the circulating blood levels of omega-3 fatty acids of 2,622 adults who were enrolled in the United States Cardiovascular Health Study.

At the beginning of this study in 1992, the participants were 74 years old, on average. Their blood levels of omega-3s were measured then, 6 years later, and 13 years later.

The types of omega-3s considered in the study were eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), and alpha-linolenic acid (ALA).

The primary food source for the first three types of omega-3s is fish — such as salmon, mackerel, tuna, herring, and sardines — and other seafood, while nuts, seeds, and plant oils contain ALA.

Lai and colleagues divided the participants into fifths, or quintiles, based on their blood levels of omega-3s.

Risk of unhealthy ageing 24 per cent lower

Overall, by the end of the study period in 2015, 89 per cent of the participants had experienced age-related chronic diseases or mental or physical dysfunction, whereas 11 per cent aged healthily.

The analysis revealed that people in the highest seafood-derived DPA consumption quintile were 24 per cent less likely to age unhealthily than those who consumed the least.

Moreover, participants in the top three DPA-consuming quintiles were 18-21 per cent less likely to experience unhealthy ageing.

Finally, seafood-derived DHA and ALA obtained from plants did not correlate with healthy ageing. Lai and colleagues point out that the study is observational and cannot explain the mechanisms responsible for these associations.

However, they believe that omega-3s may help keep blood pressure and heart rate in check, as well as reduce inflammation. Lai and colleagues conclude.

“These findings encourage the need for further investigations into plausible biological mechanisms and interventions related to [omega-3 fatty acids] for maintenance of healthy ageing, and support guidelines for increased dietary consumption of fish among older adults.”

In an editorial that accompanies the article, professor Yeyi Zhu of the Kaiser Permanente Northern California Division of Research in Oakland, CA, and her colleagues say that the new research makes “a valuable contribution” in the study of omega-3 fatty acids and ageing

However, they warn, “Epidemiologic associations cannot infer causality.” Therefore, write Prof. Zhu and her colleagues, “We caution against using these findings to inform public health policy or nutritional guidelines.”

Source: Medical News Today