Not sleeping? You’re increasing your cancer risk.

An article in Reader’s Digest states: “More research points to a correlation between not sleeping at night and a higher cancer risk. A study of women in the Danish Army, published this spring in Occupational and Environmental Medicine, found that those who worked at night had a 40 percent increased risk of breast cancer compared to those who didn’t. It’s likely the hormone melatonin, which regulates sleep cycles and may also affect estrogen levels, is to blame. Sleep deprivation at night may also suppress the immune system, allowing cancer cells to grow.”

Lack of sleep is also linked to more aggressive breast cancers in post-menopausal women, according to new findings published in the August issue of Breast Cancer Research and Treatment by physician-scientists at Case Western Reserve University. Led by Cheryl Thompson, PhD, the study shows an association between insufficient sleep and biologically more aggressive tumors as well as likelihood of cancer recurrence.