Sitting 4+ hours a day invites cancer
In a study that redefines the concept of standing up to cancer, Kansas State University researchers have found people who sit for more than four hours per day are far more likely to be diagnosed with cancer, as well as other chronic conditions such as diabetes, heart disease, and high blood pressure.
The findings, published in the International Journal of Behavioral Nutrition and Physical Activity, are based on an analysis of the health records and activity levels of more than 63,000 men — aged 45-65 years — from the Australian state of New South Wales.
Researchers divided the men into four groups, based on the amount of time they spent sitting every day: less than four hours, four to six hours, six to eight hours, or more than eight hours. They then compared their activity levels to their health histories.
The results showed those who sat for more than four hours per day were significantly more likely to report having cancer or a chronic disease, compared with those who reported sitting for less time. What’s more, researchers found the more time the men spent sitting, the greater their risk — regardless of age, income, education, weight, and height.
“We saw a steady stair-step increase in risk of chronic diseases the more participants sat,” said researcher Richard Rosenkranz, a Kansas State University assistant professor of nutrition. “The group sitting more than eight hours clearly had the highest risk."
He said the study has important implications for office desk workers and others whose jobs require them to sit for long periods of time, such as truck drivers.
"We know that with very high confidence that more physically active people do better with regard to chronic disease compared with less physically active people, but we should also be looking at reducing sitting," Rosenkranz said. "A lot of office jobs that require long periods of sitting may be hazardous to your health because of inactivity and the low levels of energy expenditure."
The take home message, he added, is that most people should get more physical activity and sit less.
"It's not just that people aren't getting enough physical activity, but it's that they're also sitting too much," he said. "And on top of that, the more you sit, the less time you have for physical activity."