- June 16, 2008 —

Science Daily/Journal of the National Cancer Institute

Low melatonin levels are associated with an increased risk of breast cancer in postmenopausal women, according to a prospective case-control study.

Melatonin is primarily secreted during the dark hours of a light-dark cycle and has been shown to be low in some night workers. Researchers have found that low melatonin levels in premenopausal women are associated with an increased risk of breast cancer.

The researchers found that women with the lowest levels of melatonin had a statistically significantly higher incidence of breast cancer than those with the highest levels.

The researchers conclude that low melatonin levels are associated with an increased risk of breast cancer. Further studies need to confirm these data and should investigate the mechanisms that underlie the association.

http://www.sciencedaily.com/releases/2008/06/080610161255.htm