A new study revealed that sitting too much is unhealthy

Jul 22, 2010 14:58 GMT  ·  By

Researchers from American Cancer Society carried out a new study that linked long sitting periods of time with a higher risk of death. This conclusion was drawn regardless of subjects' physical activity. The study appearing in the American Journal of Epidemiology, concludes that besides being physically active, people should also avoid sitting down for too long.

Because of the increasing obesity rate in the United States, more and more studies have been focusing on physical activity. Research also established links between sitting time and obesity, cardiovascular disease risk factors, type 2 diabetes and unhealthy dietary habits in children and adults, but no study focused on the link between sitting time and mortality.

To carry out this type of research, Alpa Patel, PhD and his team of scientists, analyzed questionnaires' responses from 123,216 people, of which 53,440 men and 69,776 women. These individuals had no record of cancer, stroke, heart attack or lung disease, and they took part in the American Cancer Society's Cancer Prevention II study in 1992.

The time spent sitting and physical activity related to mortality from 1993 to 2006 was analyzed. Results showed that longer sitting time is related to higher mortality risks, especially in women. Women reportedly sitting more than six hours a day had 37 percent more chances of dieing during the considered period than women who sat less than three hours a day. As for men, those who sat more than six hours a day were 18 percent more likely to die than those sitting less than three hours a day. After adding individuals' physical activity level to this data, results remained rather proportional: women and men who sat more and had little or no physical activity had 94% and 48% chances of dieing, compared to those that sat less and were more active.

Dr. Patel said that “several factors could explain the positive association between time spent sitting and higher all-cause death rates. Prolonged time spent sitting, independent of physical activity, has been shown to have important metabolic consequences, and may influence things like triglycerides, high density lipoprotein, cholesterol, fasting plasma glucose, resting blood pressure, and leptin, which are biomarkers of obesity and cardiovascular and other chronic diseases.”

The study's authors conclude that public health campaigns should also promote less sitting and more walking around, in addition to physical activity.