High Sleep Hormone Levels Lower Prostate Cancer Risk
Getting lots of sleep may lower the risk of prostate cancer, according to a new study.
Researchers found that higher levels of the sleep hormone melatonin decrease the risk of developing advanced prostate cancer.
Melatonin, a hormone that is produced only at night in the dark, plays a role in many biological processes and in regulating a variety of other hormones that influence some cancers.
"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, and/or disruption of the circadian rhythm are broad, including a potential risk factor for cancer," researcher Sarah C. Markt, M.P.H., doctoral candidate in the Department of Epidemiology at Harvard School of Public Health in Boston said in a news release. "We 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."
"Our results require replication, but support the public health implication of the importance of maintaining a stable light-dark and sleep-wake cycle," added Markt. "Because melatonin levels are potentially modifiable, further studies of melatonin and prostate cancer risk and progression are warranted."
Researchers looked at 928 Icelandic men from the AGES-Reykjavik cohort between 2002 and 2009. The men gave first morning void urine samples at recruitments and answered questionnaires about sleep patterns.
They found that men who reported taking medications for sleep, problems falling asleep and problems staying asleep had significantly lower 6-sulfatoxymelatonin levels compared with men without sleep problems.
The findings revealed that men whose 6-sulfatoxymelatonin levels were higher than the median value had a 75 percent decreased risk for advanced prostate cancer.
"Further prospective studies to investigate the interplay between sleep duration, sleep disturbance, and melatonin levels on risk for prostate cancer are needed," said Markt.
The findings were presented at the AACR-Prostate Cancer Foundation Conference on Advances in Prostate Cancer Research.