Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 106 (7)

Television Viewing and Time Spent Sedentary in Relation to Cancer Risk: A Meta-Analysis


Television Viewing and Time Spent Sedentary in Relation to Cancer Risk: A Meta-Analysis

Daniela Schmid et al. J Natl Cancer Inst.


Background: Sedentary behavior is emerging as an independent risk factor for chronic disease and mortality. However, the evidence relating television (TV) viewing and other sedentary behaviors to cancer risk has not been quantitatively summarized.

Methods: We performed a comprehensive electronic literature search in Cochrane, EMBASE, Medline, and SciSearch databases through February 2014 for published articles investigating sedentary behavior in relation to cancer incidence. Because randomized controlled trials are difficult to perform on this topic, we focused on observational studies that met uniform inclusion criteria. Data were extracted independently by both authors and summarized using random-effects meta-analysis and meta-regression. All statistical tests were two-sided.

Results: Data from 43 observational studies including a total of 68936 cancer cases were analyzed. Comparing the highest vs lowest levels of sedentary time, the relative risks (RRs) for colon cancer were 1.54 (95% confidence interval [CI] = 1.19 to 1.98) for TV viewing time, 1.24 (95% CI = 1.09 to 1.41) for occupational sitting time, and 1.24 (95% CI = 1.03 to 1.50) for total sitting time. For endometrial cancer, the relative risks were 1.66 (95% CI = 1.21 to 2.28) for TV viewing time and 1.32 (95% CI = 1.08 to 1.61) for total sitting time. A positive association with overall sedentary behavior was also noted for lung cancer (RR = 1.21; 95% CI = 1.03 to 1.43). Sedentary behavior was unrelated to cancers of the breast, rectum, ovaries, prostate, stomach, esophagus, testes, renal cell, and non-Hodgkin lymphoma.

Conclusions: Prolonged TV viewing and time spent in other sedentary pursuits is associated with increased risks of certain types of cancer.

Comment in

Similar articles

See all similar articles

Cited by 60 articles

See all "Cited by" articles

Publication types

MeSH terms