New Study: Eating More Plant Foods Could Increase Lifespan by up to 13 Years

Incorporating more fruits, vegetables, legumes, whole grains, and nuts into your diet could increase your lifespan by a decade or more, according to new research published this week in PLOS Medicine. 

Researchers used data from the 2019 Global Burden of Disease study to assess the impact of various food groups on life expectancy. They then created a model to understand what might happen if someone transitioned from a standard Western diet to an “optimal diet” that included more fruits, vegetables, whole grains, nuts, legumes, and fish and fewer red and processed meats, refined grains, and sugar-sweetened beverages. 

According to the research, women who made a sustained change from the standard Western diet to the optimal diet starting at age 20 could expect to add 10 years to their lives, while men who started eating healthier at that age could tack on an extra 13 years. But the benefits don’t only apply to young adults: The data also showed women who made the switch at age 60 could add eight more years to their lives, while men could add nine. Even 80-years-olds can reap the rewards of a plant-forward diet and increase their lifespan by 3.5 years if they cut out red meat, refined sugar, and highly processed foods, according to the model. 

The study authors noted that the largest gains to life expectancy would be made by eating more legumes, whole grains, and nuts. 

"The notion that improving diet quality would reduce the risk of chronic disease and premature death is long established, and it only stands to reason that less chronic disease and premature death means more life expectancy," Dr. David Katz, MPH, FACPM, FACP, FACLM, told CNN. Katz, who is president and founder of the preventive and lifestyle medicine nonprofit True Health Initiative, was not involved in the study.

"What they define as an 'optimal' diet is not quite optimal; it's just a whole lot better than 'typical,'" Katz said. “My impression is that their 'much improved' diet still allowed for considerable doses of meat and dairy," Katz added, acknowledging that when his team scores diet quality objectively, "these elements are at quite low levels in the top tier."

This new study is further confirmation that diet can significantly impact life expectancy. Nearly 1 in 5 deaths around the world are caused by poor nutrition every year, particularly in populations with diets low in whole grains, fruits, nuts, and seeds. A 2019 study published in The BMJ followed the food and drink consumption of nearly 20,000 people for 15 years to determine the impact on all-cause mortality. The researchers discovered that high consumption of ultra-processed foods led to a 62 percent increase in the chance of premature death compared to those who ate the fewest ultra-processed foods. Additionally, the CDC released a report in January 2022 that found only 12 percent of American adults met the daily fruit intake recommendations and a mere 10 percent met the daily vegetable intake guidelines. 

The good news? This recent research confirms that small changes toward the “optimal diet” are effective at increasing your lifespan even if you don’t completely overhaul your eating patterns. Apart from extending your life, plant-based diets are associated with using fewer medications in old age, better sexual health, and lower rates of cancer. 

To learn more about a whole-food, plant-based diet, visit our Plant-Based Primer. For meal-planning support, check out Forks Meal Planner, FOK’s easy weekly meal-planning tool to keep you on a healthy plant-based path.