Research we're watching: Want to extend your life? Avoid too much sitting

Spending too much time each day sitting behind a desk or lying on the couch watching TV could contribute to an early demise, according to a study published in January in the American Journal of Preventive Medicine. The study involved more than 92,000 postmenopausal women, ages 50 to 79. Women who spent more than 11 hours out of every day sitting or lying down had a 12% higher risk of premature death from all causes—including heart disease and cancer—than women who were inactive for four hours or less.

Even habitual exercisers were at greater risk for dying if they also spent long stretches of time sitting, suggesting that too much sitting, regardless of other exercise, raises one's risk of premature death, says Dr. JoAnn Manson, one of the study's authors and chief of preventive medicine at Harvard-affiliated Brigham and Women's Hospital. "Once you're sitting for more than six to eight hours a day, that's not likely to be good for you," she says. Dr. Manson recommends that if you're engaged in a sedentary activity such as working a desk job or watching TV, set an alarm on your clock or smartphone to ring once every 30 to 60 minutes. When the alarm goes off, get up and walk around for a couple of minutes to avoid prolonged periods of inactivity.