The new health phrase, "Sitting is the new smoking," is not an exaggeration, according to the October issue of Mayo Clinic Health Letter. Most people don't smoke, but everyone sits -- and most sit too long each day. Many U.S. workers sit for 15 hours a day.
In the past 15 years, a wave of research has shed new light on sitting as a serious health risk, even in those of normal weight and who routinely exercise. Thirty-four chronic conditions and illnesses have been associated with excess sitting. One recent study compared adults who spent less than two hours a day watching television with those who spent more than four hours a day doing so. After adjusting for obesity, age and other risk factors, those with higher screen time had:A 52 percent greater risk of dying during the study Over two times the risk of having a cardiovascular event, such as chest pain (angina), heart attack, heart failure and stroke
In a review of research related to sitting and cancer, each two-hour-a-day increase in sitting time was related to:An 8 percent increased risk of colon cancer A 10 percent increased risk of endometrial cancer A 6 percent increased risk of lung cancer
Other research has shown that too much sitting can negate many of the health benefits of moderate exercise. One study compared adults who spent less than one hour a day watching television to those who spent seven or more hours a day watching television. People who watched the most television had a 68 percent greater risk of dying during the study than those who watched the least. The risk of death decreased slightly, to 61 percent, in those who watched seven or more hours of television and exercised moderately an hour a day. Calculated another way, the study authors estimated that one hour of continuous sitting negated the benefit of 15 minutes of moderate exercise.
The studies are preliminary and need to be validated to provide a clearer view of the risks associated with sitting. But the underlying message is increasingly clear. Daily exercise is important for health but it's also important to be mindful of sitting.