Inadequate Sleep Increases Prostate Cancer Risk

Scientists have alerted that sleeping less than five hours a night could make a person twice as likely to develop prostate cancer. According to data published in ‘Cancer Epidemiology’, men younger than 65, who are not getting the recommended seven hours of sleep are raising their risk of the disease by 55 per cent.

Prostate cancer, also known as carcinoma of the prostate, is the development of cancer in the prostate, a gland in the male reproductive system. Most prostate cancers are slow growing; however, some grow relatively quickly. The cancer cells may spread from the prostate to other parts of the body, particularly the bones and lymph nodes.

The study, conducted at the American Cancer Society in Atlanta, Georgia in the United States, examined data from two large, long-term cohort studies. The first study followed more than 407,000 men between 1950 and 1972, while the second followed more than 416,000 men from 1982 to 2012. All the men were cancer-free when the studies began. However, more than 1,500 men in the first study and more than 8,700 men in the second study died of prostate cancer during the follow-up periods.

Afterwards, the researchers studied the men’s sleeping patterns. During the first eight years of follow-up, men younger than 65 years old, who slept between three and five hours per night had a 55 per cent greater risk of dying from prostate cancer than those who slept seven hours per night. And six hours of sleep a night was linked to a 29 per cent higher risk of prostate cancer death compared to seven hours, as prescribed by the National Sleep Foundation.

Those who were age 65 or older showed no difference in the risk of death from prostate cancer, no matter how much sleep they got. Lead study author, Dr. Susan Gapstur and vice president of epidemiology at the American Cancer Society, said, “If confirmed in other studies, these findings would contribute to evidence suggesting the importance of obtaining adequate sleep for better health.” He added, however, that more research is needed to better understand the biologic mechanisms; so, sleep-deprived males shouldn’t be alarmed just yet. Still, the findings contribute to evidence that the body’s natural sleepwake cycle – called circadian rhythm – might play a role in prostate cancer development.

Not only does poor sleep turn off genes that protect against cancer growth, but past research has found that not getting enough shuteye can inhibit production of melatonin, a hormone that controls the sleep-wake cycle.
Low levels of melatonin can lead to an increase in genetic mutations, reduced DNA repair and a weakened immune system, according to Gapstur. And although the link between limited sleep and prostate cancer isn’t clear, Gapstur says a possibility is that the natural decline in night time melatonin levels as you age can reduce the relative impact of lack of sleep.