Over the years as I have practiced in Las Vegas (the town that never sleeps) I have repeatedly found that when casino workers are on rotating shifts their health is affected adversely. And only after I insist they get onto a set schedule whether graveyard or daytime or swing shift do they do much better. So when I saw this new study out of Japan that linked prostate cancer to a rotating work schedule I was not surprised.
The Japanese study found that men who alternate between daytime and nighttime shifts on their jobs have triple the normal rate of prostate cancer. It is postulated that this variable schedule upsets daily hormone production cycles. Previous studies have shown a link to breast cancer and colorectal cancer in women who worked variable schedules.
The hormone most likely affected is melatonin which has been shown to have anti-cancer effects on breast cancer. So it makes sense that melatonin also protects against prostate cancer.
Ayurvedic medicine which is over 2,000 years old has always recognized the value of keeping our body on a fixed schedule. Unfortunately, modern medicine has to relearn this common sense principle itself by doing studies.