Just How Much of a Benefit Do We Get from a Healthful Lifestyle?

Virtually everyone knows that a healthful lifestyle — never smoking, normal body-mass index (BMI), moderate-to-vigorous physical activity, moderate alcohol intake, and a higher-quality diet — is good for their health. What very few people know is just how much benefit they get from achieving all these lifestyle goals.

A Harvard team examined data from about 111,000 people at age 50 and followed them prospectively for as long as 34 years. Healthful lifestyle factors were measured repeatedly and systematically, and development of various diseases and death were recorded. The primary endpoint was life expectancy free from diabetes, cardiovascular diseases, and cancer. Women who met all the healthful lifestyle measures had an additional 10.7 yea…