This will be challenging for many, however. It means giving up red and processed meat, and embracing lentils, beans, and peas instead.
For those reluctant to abandon their juicy steaks and hot dogs, the authors suggest a compromise, eating what’s called a "feasibility diet." The good news: even this more modest change can significantly increase life expectancy.
There are thousands of studies that show how food choices affect our health, but researchers at the University of Bergen in Norway took a different approach.
"Research until now," explains Lars Fadnes, first author of the new study, "has shown health benefits associated with separate food groups or specific diet patterns but given limited information on the health impact of other diet changes. Our modeling methodology has bridged this gap.”
For their study the researchers brought together a vast and comprehensive amount of data to estimate how life expectancy varies with sustained changes in a dozen different food groups.
For Best Results Start Young
Moving from a typical Western diet to an optimized diet from age 20 would increase life expectancy by 10.7 years for women and 13 years for men.Doing the same at age 60 would provide an extra eight years of life for women and 8.8 years for men. At age 80 the increases for both men and women are 3.4 years.
Meanwhile, changing from a typical diet to a feasibility diet, which sits half-way between the typical Western diet and an optimized diet, would still add years to your life - an estimated 6.2 years of life for a 20-year-old woman and 7.3 years for a 20-year-old man. Even more exciting, changing to a feasibility diet increases life expectancy by seven percent or more for both sexes across all age groups.
How to Change Your Diet
If you choose the optimized diet, researchers say you must completely cut out red meat, processed meats, and sugary drinks. You must reduce your intake of eggs, milk or dairy products, refined grains, and white meat.Instead, you want to eat more whole grains, vegetables, fruits, nuts, legumes, and fish.
Meanwhile, the feasibility approach allows for 50 grams of meat per day, 25 grams of processed meat and 250 grams of sugar-sweetened drinks.
There's nothing particularly remarkable about these findings. In fact, the research supports the kind of dietary health advice that's been recommended for some time, but there is one surprise.
Take note, the authors write, that in both diets "the largest (longevity) gains would be made by eating more legumes (beans, peas, lentils), whole grains and nuts, and less red meat and processed meat."
But that’s not all…
Longevity Diets go Beyond Fruits and Vegetables
The biggest recommended change when switching from a typical Western diet to an optimized diet is to eat more whole grains, legumes, and fish rather than fruits and vegetables.This recommendation might appear to fly in the face of the standard advice on healthy eating, but there’s more to it than meets the eye. According to these researchers, the daily whole grain consumption should be more than quadrupled to 225 grams a day, while legumes should rise to 200 grams from a typical zero. Fish consumption quadruples to 200 grams a day.
Vegetables, on the other hand, need to be increased by “only” 60 percent and fruit by 100 percent to 400 grams each (ten a day rather than five a day).
The reason, as explained by Professor Fadnes, is that people have been making changes to their diet to incorporate more fruit and vegetables, so they have "already harvested some of the benefits" but have yet to do so for other food groups.
If you’re interested in trying this approach and need some more motivation, the study authors have developed an online calculator so you can see for yourself how dietary improvements will impact your lifespan. It's available at http://www.food4healthylife.org/
