Healthy lifestyle habits not only improve life expectancy, they may also extend the number of years one lives free of type 2 diabetes, heart disease and cancer, according to a new study from Harvard. 

The researchers analyzed health data from more than 100,000 participants in two major prospective studies. They found that at middle age, eating a healthy diet, exercising regularly, keeping a healthy body weight, not drinking too much alcohol, and not smoking were key to keeping chronic conditions at bay.

Women who practiced four or five of these healthy habits at age 50 on average lived about 34 years free of chronic disease. This finding compared to about 24 healthy years among women who practiced none. Meanwhile, men who practiced four or five of these habits at age 50 lived 31 years free of chronic disease, compared to about 23 years among men who practiced none.

Participants with the lowest disease-free life expectancy were men who were current heavy smokers, and men and women with obesity, wrote Yanping Li, from the Harvard T.H. Chan School of Public Health.

“This study provides strong evidence that following a healthy lifestyle can substantially extend the years a person lives disease-free,” Li said.

The researchers deemed a diet healthy if it scored high on the Alternate Healthy Eating Index. Regular exercise was defined as at least 30 minutes per day of moderate to vigorous activity, and healthy weight as a body mass index of 18.5-24.9 kg/m2. Moderate alcohol intake was established as up to one serving per day for women and up to two for men.

Data was culled from the Nurses’ Health Study and the Health Professionals Follow-up Study.

An article was published in The BMJ