A review from the AANP:
TUES., JAN. 21, 2014: JUST-RELEASED NATURAL HEALTH STUDYMELATONIN MAY LOWER PROSTATE CANCER RISK: New evidence suggests that higher levels of melatonin, a hormone involved in the sleep-wake cycle, may decrease the risk for developing advanced prostate cancer. (Melatonin is a hormone produced exclusively at night in the dark and is an important output of the inherent 24-hour clock. Many body processes are regulated by the circadian rhythm, including sleep-wake cycles.) Sleep loss and other factors can influence the amount of melatonin secretion or block it altogether, and health problems associated with low melatonin, disrupted sleep, or disruption of the circadian rhythm are broad, including a potential risk factor for cancer. To investigate the association between urine levels of the main breakdown product of melatonin, 6-sulfatoxymelatonin, and the risk of prostate cancer, the researchers conducted a study of 928 men. The study team found that men who had higher levels of melatonin had a 75 percent reduced risk for developing advanced prostate cancer compared with men who had lower levels of melatonin. These results were presented in San Diego on January 21, 2014 at the AACR-Prostate Cancer Foundation Conference on Advances in Prostate Cancer Research. The study has not yet been published in a journal or posted online.