Spending more leisure time sitting is associated with a higher risk of multiple myeloma, breast cancer and ovarian cancer in women, a new large-scale study led by an Indian-origin scientist has found.
The study, however, found no association between sitting time and cancer risk in men.
While extensive research links physical activity to cancer prevention, few studies have examined the link between sitting time and the risk of specific cancers.
For the study, researchers led by Alpa Patel from American Cancer Society, compared leisure time sitting to cancer risk among more than 146,000 men and women (69,260 men and 77,462 women) who were cancer-free and enrolled in the American Cancer Society Cancer Prevention Study II Nutrition Cohort.
Between 1992 and 2009, 18,555 men and 12,236 women were diagnosed with cancer.
The researchers found longer leisure-time spent sitting was associated with a 10 per cent higher risk of cancer in women after adjustment for physical activity, Body Mass Index (BMI) and other factors. The association was not apparent in men.
In women, sitting time was specifically associated with risk of multiple myeloma, invasive breast cancer, and ovarian cancer. Among men no association between sitting time and site-specific cancers was found.
"Longer leisure-time spent sitting was associated with a higher risk of total cancer risk in women, and specifically with multiple myeloma, breast and ovarian cancers, but sitting time was not associated with cancer risk in men," the researchers concluded.
"Further research is warranted to better understand the differences in associations between men and women," they said.
The study was published in the journal Cancer Epidemiology, Biomarkers and Prevention.
