Dietary risk factors are estimated to lead to 11 million deaths and 255 million years of healthy life lost each year. However, research published last month found that dietary changes can add more than ten years to a person’s lifespan.

Lars Fadnes, Professor of Global Public Health at the University of Bergen, Norway, says: “Research so far has shown health benefits associated with distinct food groups or specific diets, but gives limited information on the health impact of other dietary changes.

“Our modeling methodology filled this gap.”

Professor Fadnes’ research team used existing meta-analyses and data from the Global disease burden study to build a model to estimate the effect of a series of dietary changes on life expectancy. The model was developed to build a Food4HealthyLife calculator that could be a useful tool for clinicians, policy makers and laypersons to understand the health impact of food choices.

The team based their findings on the US diet, but the results for the Chinese and European diets were broadly similar.

The model predicts that a sustained change from a typical Western diet to an optimal diet starting at age 20 would increase life expectancy by an average of 10.7 years for women and 13 years for men. For older people, the gains are smaller but still substantial.

Switching to the optimal diet at age 60 could further increase life expectancy by eight years for women and 8.8 years for men. Even people in their 80s could gain an additional 3.4 years from such dietary changes.

Health gains from dietary changes were mainly due to reduced deaths from cardiovascular disease, cancers and diabetes. All of these are among the leading causes of death worldwide.

“Understanding the relative health potential of different food groups could enable people to achieve achievable and significant health gains,” the study authors wrote.

An optimal diet had a significantly higher intake than a typical diet of whole grains, legumes, fish, fruits, vegetables and included a handful of nuts, while reducing red and processed meats, sugary drinks and refined cereals. Other foods like eggs, dairy, white meat, and oils don’t seem to have a measurable effect on longevity.

Analyzes have also shown strong positive health benefits of eating fruits, vegetables and fish. However, the team found that the typical intake of these foods, especially vegetables, was closer to the optimal intake than for other food groups. A finding that will surprise most Australian nutritionists.

“Our sentence on fruit, vegetable and fish consumption being closer to optimal intake than the legumes, whole grains and nuts food groups, might have been a bit fuzzy,” Professor Fadnes said. get started.

“For fruits, vegetables and fish, we estimate the benefits of doubling the intake from the initial intake levels. The difference was mainly that for legumes, whole grains and nuts, the levels initial intakes were estimated to be even worse, and therefore the benefits of optimizing them were even greater,”

The team recognized that an ideal diet might not be practical for everyone, so they suggested a feasibility approach diet that was halfway between an optimal diet and a typical Western diet. They say this diet produces longevity estimates that are closer to what we might reasonably expect by modifying most people’s diets in most settings.

They cautioned that the study’s methodology provides estimates of increased population longevity and is not intended to predict individual longevity.

Even though the diets were relatively similar in energy, energy differences may have played a role in the relationships of the analyzes they studied. Nevertheless, optimal diets are likely to reduce the risk of obesity/overweight and can have a significant impact on health-related quality of life. Although the team did not model non-fatal effects, life expectancy is correlated with healthy life years.

Sensitivity analyzes were used to estimate how changes in life expectancy due to dietary changes vary whether the true effects are overestimated or underestimated. Even the most conservative approaches point to large effects, they said.

The study was published last month in OLP Medicine.