Harvard Women's Health Watch

Sitting may increase risk of early death

Even an hour's exercise a day won't protect you from an earlier death, if you spend most of the rest of your day sitting. That's the verdict of Canadian researchers who pored over data from 47 studies on the effects of sedentary behavior. When they combined the results of all the studies, the researchers found that regardless of their levels of physical activity otherwise, people who sat for long periods had an increased risk of developing a host of diseases. People who sat the longest had a 24% greater risk of dying, an 18% greater risk of heart disease, a 13% greater risk of cancer, and a 90% greater risk of diabetes. The results were published in the Jan. 20, 2015, issue of Annals of Internal Medicine.

The researchers recommend standing for a minute or two every half‑hour when you have a task that keeps you chair‑bound. It may help to set a timer or alarm to sound at half-hour intervals.

Exactly how sitting contributes to poor health isn't clear. Some research suggests that it has harmful effects on sugar and fat metabolism, both of which affect a person's risk of diabetes and heart disease. And you do burn 30% more calories when you're standing than when you're sitting.