By Sandee LaMotte, CNN
February 9, 2022

(CNN) - Changing what you eat could add up to 13 years to your life, according to a newly published study, especially if you start when you are young.
The study created a model of what might happen to a man or woman's longevity if they replaced a "typical Western diet" focused on red meat and processed foods with an "optimized diet" focused on eating less red and processed meat and more fruits and vegetables, legumes, whole grains and nuts.

If a woman began eating optimally at age 20, she could increase her lifespan by just over 10 years, according to the study published Tuesday in the journal PLOS Medicine. A man eating the healthier diet from age 20 could add 13 years to his life.

Focusing on a healthier diet could also lengthen the lives of older adults, the study said. By starting at age 60, a woman could still increase her lifespan by eight years. Men starting a healthier diet at age 60 might add nearly nine years to their lives.

A plant-based eating style could even benefit 80-year-olds, the study said: Men and women could gain about 3.5 years of extra life from dietary changes.

"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," said Dr. David Katz, a specialist in preventive and lifestyle medicine and nutrition, who was not involved in the study.

Katz, the president and founder of the nonprofit True Health Initiative, a global coalition of experts dedicated to evidence-based lifestyle medicine, has published research on how to use food as preventive medicine.