Levothyroxine and colorectal cancer.

Thyroxine is one of major hormones controlling metabolism levels. According to population-based matched case–control study (2566 pairs) in northern Israel ^the use of levothyroxine was associated with a statistically significantly reduced relative risk of CRC (odds ratio = 0.59, 95% confidence interval = 0.43 to 0.82, P = .001). This association remained statistically significant after adjustment for age, sex, use of aspirin and statins, sports activity, family historyof CRC, ethnic group, and level of vegetable consumption (odds ratio = 0.60, 95% confidence interval = 0.44 to 0.81, P = .001).

A Case–Control Study of Levothyroxine and the Risk of Colorectal Cancer

Gad Rennert, Hedy S. Rennert, Mila Pinchev, Stephen B. Gruber