Breast Cancer and Electric Light

This article discussed a recent connection made between exposure to electric light (at night) and breast cancer. The connection stems from the fact that light exposure during darkness hours interferes with women's ability to produce melatonin, a hormone that manages the body's day and night rhythms.

David Blask, who lead the study, explains: "melatonin puts cancer cells, in particular breast-cancer cells, to sleep at night, but if the levels of this hormone are diminished by exposure to light at night, cancers become insomniacs and grow all the time."

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