Adopting diets to prevent diabetes in your 40s could be key to staying fit and mentally fit in your 70s, research suggests.
Eating plenty of vegetables, whole grains and lean meats in middle age has been found to help keep chronic disease and cognitive decline at bay decades later.
The study, which involved more than 100,000 people over 30 years, found that those who followed one of eight healthy dietary patterns were up to 84 percent more likely to function well at age 70.
Harvard University experts said the links remained strong even when other lifestyle factors were taken into account, stressing that diet should be used to promote healthy ageing.
Although previous studies have shown that healthy lifestyles can help prevent chronic diseases, here researchers looked at the absence of disease along with the ability to live independently with a good quality of life.
Eating plenty of vegetables, whole grains and lean meats in middle age has been found to help keep chronic disease and cognitive decline at bay decades later.
They analyzed data from more than 106,000 people since 1986, based on dietary questionnaires administered every four years.
Participants were at least 39 years old and had no chronic diseases at the start of the study.
Researchers compared rates of healthy aging between people in the top 20 percent and the bottom 20 percent of adherence to healthy dietary patterns.
By 2016, nearly half had died and only 9.2 percent survived to age 70 or older, disease-free and in good physical, cognitive and mental health.
Those who ate more fruits, non-starchy vegetables, whole grains, unsaturated fats, nuts, legumes and low-fat dairy products were 84 percent more likely to age well compared to those who ate the least.
Meanwhile, a low-carb diet called “hyperinsulinemia” (named for the condition in which the body has too much insulin and often recommended to type 2 diabetics) increased the odds by 78 percent.
The planetary health diet, which typically consists of half a plate of fruits and vegetables and the other of whole grains, plant proteins such as beans, lentils, legumes, nuts and small amounts of meat and dairy products, came in next at 68 percent.
Harvard University experts said the links remained strong even when other lifestyle factors were taken into account, stressing that diet should be used to promote healthy ageing.
This was closely followed by the Mediterranean diet, which typically includes two to three servings of fish a week, while a predominantly plant-based diet was associated with a 43 percent greater chance of aging well.
Those who had higher intakes of trans fats, sodium, total meats, red meats and processed meats had lower chances of healthy aging, according to findings presented at the Nutrition conference in Chicago.
Lead author Dr Anne-Julie Tessier said: ‘People who followed healthy dietary patterns in midlife, especially those rich in fruits, vegetables, whole grains and healthy fats, were significantly more likely to achieve healthy ageing.
‘This suggests that what we eat in middle age may play an important role in aging.’