Want to add a decade to your life? It's time to consider ditching red and processed meat and stocking up on lentils.
If at 20 years old we stuck to a diet full of nuts, pulses and grains, then we could enjoy ten more years than if we abided by a typical Western diet, containing hardly any legumes, too few fruits and vegetables, and too much dairy and sugary drinks, new research suggests.
While making the change earlier has the greatest impact on lifespan, a switch to an 'optimal' diet at the age of 60 could still gain us more than eight extra years, and even at 80 could gain us more than three years, scientists say.
"Food is fundamental for health, and globally, dietary risk factors are estimated to cause 11 million deaths and 255 million disability-adjusted life years annually," Lars Fadnes, the one of the study's researchers from the University of Bergen, Norway, said.
By comparing a 'typical Western diet' with an 'optimal' diet for health, and putting them through a computer simulation, researchers were able to determine health risks by age and food, with the largest gains found to be from eating more legumes, which include foods like lentils, as published in PLoS One.
Eating more legumes would add about 2.3 years of life expectancy for both men and women combined, eating more whole grains would lead to 2.2 additional years, while more nuts would add just under two.
What the scientists describe as an 'optimal' diet would include 225g of whole grains, 200g of fish, 200g of legumes and 400g of vegetables per day, without red meat, sugary drinks or processed meat.
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Researchers have created the 'Food4HealthyLife' calculator, available online, in order to help clinicians, policy makers, and anyone who's interested to learn about the health impact of dietary choices, and the effect it has on life expectancy.
"Understanding the relative health potential of different food groups could enable people to make feasible and significant health gains," said Fadnes.
Foods like beans, lentils and peas are a low-fat source of protein, fibre, vitamins and minerals, and count towards your recommended five a day. They can be a great option for people who aren't getting protein or iron from meat, and can contribute to a healthy lifestyle.
Cancer Research UK estimates more than six in 10 adults are overweight or obese in the UK, which can develop as a result of factors including poor diet, such as eating large amounts of processed or fast food, drinking too many sugary drinks or eating larger potions than needed.
Speaking on the legumes study, Andrew Steele, author of Ageless: The New Science of Getting Older Without Getting Old, told The Times, "Maybe people who are eating 200 grams of lentils a day are just systematically different from people who are eating large amounts of red meat. That's a lot of lentils."
However, he added, "We do know that changes in lifestyle can have an impact that stretches for years, even a decade. And these changes are quite major."