Regular exercise is essential for overall health and well-being, but if you have a sedentary job or like to spend long hours vegging in front of the TV, be forewarned: the time you spend sitting at your computer or slouched on your couch is putting you at risk.
A growing body of evidence shows that sitting — no matter how much time you spend exercising — increases your risk of cancer.
An analysis of 43 observational studies published in the Journal of the National Cancer Institute in 2014 found sedentary behavior was associated with a 24 percent greater risk of developing colon cancer, a 32 percent higher risk of endometrial cancer, and a 21 percent increased risk of lung cancer.
The effects of sitting may be especially detrimental for women. Last year researchers from the American Cancer Society published a study that found women who spend six hours or more of free time sitting per day have a 10 percent greater risk of getting cancer than those who spend less than three hours of free time sitting per day. They were also more likely to develop certain types of cancer: multiple myeloma, ovarian cancer, and invasive breast cancer.
In the study, sitting time increased cancer risk for men only if the men were obese. The study analyzed information from 77,462 women and 69,260 men enrolled in the American Cancer Society Cancer Prevention Study II Nutrition Cohort.
Sitting may increase cancer risks because it promotes weight gain and obesity, which are related to increased risk of cancer. Obesity promotes cancer-causing processes such as insulin resistance, systemic inflammation, and the production of certain hormones linked to tumor formation. It also reduces Vitamin D levels, which are believed to protect against colon cancer.
“Increasingly the research shows that a sedentary lifestyle isn’t just bad for your cardiovascular health, it increases your risk of certain types of cancers,” says Dr. Dan Flora, a medical oncologist with OHC. “Because many people work in sedentary jobs and enjoy sedentary recreational activities, it’s important to make a concerted effort to stand more often both at work and at home.”
The ACS offers these tips to reduce the amount of time you spend sitting:
- Making short meetings “standing” meetings, if you’re the organizer
- Stand during conference calls
- Try eating lunch standing at a counter, rather than sitting at a table
- Taking a 1-2 minute standing or walking break every hour
- Try standing when you watch TV or check your email.
