Did you know, for example, that long stretches of shift work may increase cancer risk.

Johns Hopkins Medicine »

Long-term sleep disruptions may raise the risk of some cancers. But sleep and cancer are intertwined in other ways too. Getting a good night’s sleep is difficult during cancer treatment and can be a lifelong challenge for survivors.

“In our research, nearly one in four survivors of childhood cancer had difficulty falling asleep and staying asleep,” says cancer expert Kathryn Ruble, M.S.N., Ph.D. , of the Johns Hopkins Kimmel Cancer Center . “Helping cancer survivors improve their sleep might help them perform at school, on the job, and throughout their lives.”

Disruptions in the body’s “biological clock,” which controls sleep and thousands of other functions, may raise the odds of cancers of the breast, colon, ovaries and prostate. Exposure to light while working overnight shifts for several years may reduce levels of melatonin, encouraging cancer to grow.