Diet change could add up to a decade of life expectancy

Our elders unsurprisingly lived up to eighty years and more, even without much medication or hospitalization, while the youth nowadays grapple with heart diseases, diabetes, obesity, blood pressure, and whatnot. But, according to a new study, a young adult could add more than a decade to their life expectancy by changing their diet from a typical Western diet to an optimized diet that includes more legumes, whole grains and nuts, and less red and processed meat.

The study was published in 'PLOS Medicine' by Lars Fadnes of the University of Bergen, Norway, and colleagues.

For older people, the anticipated gains to life expectancy from such dietary changes would be smaller but still substantial.

Food is fundamental for health and, globally, dietary risk factors are estimated to lead to 11 million deaths and 255 million disability-adjusted life-years annually.

In the new study, researchers used existing meta-analyses and data from the Global Burden of Diseases study to build a model that enables the instant estimation of the effect on life expectancy (LE) of a range of dietary changes. The model was also available as a publicly available online tool called the Food4HealthyLife calculator (https://food4healthylife.org/).

For young adults in the United States, the model estimated that a sustained change from a typical Western diet to the optimal diet beginning at age 20 would increase LE by more than a decade for women (10.7 [uncertainty interval 5.9-14.1] years) and men (13.0 [6.9-17.3] years).

The largest gains in years of LE would be made by eating more legumes (females: 2.2 [1.0-3.4]; males: 2.5 [1.1-3.9]), more whole grains (females: 2.0 [0.7-3.3]; males: 2.3 [0.8-3.8]), and more nuts (females: 1.7 [0.8-2.7]; males: 2.0 [1.0-3.0]), less red meat (females: 1.6 [0.7-2.5]; males: 1.9 [0.8-3.0]) and less processed meat (females: 1.6 [0.7-2.5]; males: 1.9 [0.8-3.0]).

Changing from a typical diet to the optimized diet at age 60 years could still increase LE by 8.0 (4.8-11.2) years for women and 8.8 (5.2-12.5) years for men, and 80-year-olds could gain 3.4 years (females: 2.1-4.7 and males: 2.1-4.8) from such dietary changes.

"Understanding the relative health potential of different food groups could enable people to make feasible and significant health gains," the authors said. "The Food4HealthyLife calculator could be a useful tool for clinicians, policymakers, and lay-people to understand the health impact of dietary choices."

Fadnes added, "Research until now have shown health benefits associated with separate food group or specific diet patterns but given limited information on the health impact of other diet changes. Our modelling methodology has bridged this gap."