“There have been some concerns that one of the reasons why breast cancer may be more common in developed countries compared with developing countries is differences in bra-wearing patterns,” explains Lu Chen, MPH, a researcher in the Public Health Sciences Division at Fred Hutchinson Cancer Research Center and a doctoral student in the Department of Epidemiology at the University of Washington School of Public Health, both in Seattle. The National Center For Health Research say the rumor that bras cause breast cancer was fueled by a 1995 book by Sydney Ross Singer and Soma Grismaijer called Dressed To Kill. In it, the authors claim that women who wear underwire bras for 12 hours a day have a much higher risk of developing cancer than women who do not wear bras. They consider that, by restricting the lymph system, bras cause toxins to build up in the breasts that eventually result in cancer.
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