The Philadelphia Inquirer
MONDAY, May 28 (HealthDay News) -- Women who work the night shift more than twice a week might be increasing their risk for breast cancer, Danish researchers find.
Moreover, the risk appears to be cumulative and highest among women who describe themselves as "morning" people rather than "evening" people, the researchers say."About 10 to 20 percent of women in modern societies have night shift work," said lead researcher Johnni Hansen. "It might therefore be one of the largest occupational problems related to cancer."
Right now, the reasons for these findings are uncertain.
"Night shift work involves exposure to light at night, which decreases the production of the night hormone melatonin that seems to protect against certain cancers," said Hansen, of the Institute of Cancer Epidemiology at the Danish Cancer Society, in Copenhagen... Read More