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5 Health Risks of Too Little Sleep

Colon Cancer

A ground-breaking new study published in the journal Cancer has found that people who sleep less than six hours per night on average had an almost 50 percent increase in the risk of colorectal adenomas compared with individuals who got at least seven hours a night. (Adenomas are a precursor to cancer tumors, and if left untreated, can turn malignant.) The study's principal investigator, Li Li, MD, PhD, said that the increase in risk due to less hours of sleep is comparable to the risk associated with having a first-degree relative (parent or sibling) with colon cancer, as well as with high, red meat intake. Although why less sleep may lead to colon cancer is unknown, Dr. Li said some of theories include that less sleep may mean less production of melatonin, a natural hormone that in animals has been linked to DNA repair, or that insulin resistance may underlie the link between sleep disturbance and cancer development.