Lowering mortality risks? Mediterranean diet study hones in on biomarkers for seniors

24 Jan 2022 --- The Mediterranean diet has been linked to a lower mortality risk in adults over 65. A new longitudinal study of 642 participants found that the score of the Mediterranean diet using specially formulated biomarkers was inversely associated with all causes of death.

“This supports the use of these biomarkers in monitoring evaluations to study the health benefits associated with the Mediterranean diet,” says Tomás Meroño, co-first signatory of the study.

Notably, the analysis of dietary biomarkers in plasma and urine can contribute to the individualization of food assessment for older people.

This taps into the burgeoning personalized nutrition trend, which has gone from a niche industry positioning to a mainstay. Notably, the NIH is granting US$170 million in funding over the next five years for precision nutrition studies.The Mediterranean diet generally includes high levels of whole grains, vegetables, legumes, fruits, nuts and seeds, with moderate levels of seafood, dairy and poultry.  

Additionally, it is currently the Decade of Healthy Ageing, with the World Health Organization (WHO) spotlighting the role of nutrition in maintaining vitality.

Selecting biomarker reference levels
The researchers developed an index of dietary biomarkers based on food groups that are part of the Mediterranean diet, and assessed their association with mortality, explains Cristina Andrés-Lacueva, who led the study.

In the study, researchers chose the reference levels of various dietary biomarkers in the urine.

These included total polyphenols and resveratrol metabolites (from grape intake) and presents in plasma, plasma carotenoids, selenium, vitamin B12, fatty acids and their proportion of monounsaturated and saturated fatty acids.

Using a predictive model, they assessed the associations of the Mediterranean diet index and the food-frequency questionnaire (FFQ) with mortality.

“We confirm that an adherence to the Mediterranean diet assessed by a panel of dietary biomarkers is inversely associated with long-term mortality in older adults,” says Meroño.

Spotlight on Tuscany
The researchers are based at the University of Barcelona (UB) and the CIBER on Fragility and Healthy Ageing (CIBERFES), also formed by the Food Innovation Network of Catalonia (XIA). The paper is also carried out in collaboration with the National Institute on Aging (NIA) of the US.

The study is based on the InCHIANTI project, conducted in the Italian region of the Tuscany. The study has been carried out across twenty years among a total of 642 participants (56% women) aged over 65 or more. This enabled the researchers to obtain complete data on food biomarkers.

During twenty years of monitoring, there were 425 deaths (139 due to cardiovascular diseases and 89 due to cancer-related causes).

In 2020, researchers uncovered biomarkers explaining the longstanding link between Mediterranean diets and lowered risk of Type 2 diabetes.

However, a separate study found that benefits of a Mediterranean diet on cognitive health are diminished when unhealthy foods are also eaten.

Edited by Katherine Durrell