According to a new study by epidemiologist Lynn Rosenberg of Boston University's Slone Epidemiology Center. Rosenberg and her team studied 48,167 black women from all over the country who replied to questionnaires mailed out every two years. The women in the Black Women's Health Study were aged 21 to 69 when the study began in 1995. Rosenberg tracked what happened to women who used hair relaxers containing lye (sodium hydroxide), calcium hydroxide, guanidine carbonate, or thioglycolic acid between 1997 and 2003.
“These substances are not known carcinogens, but because the US Food and Drug Administration does not monitor all ingredients in cosmetics, there is no way to tell for certain that hair relaxers are safe. These substances are so widely used by black women that we felt it was important to do our study,” she said.
“We found absolutely no increased risk of breast cancer with hair relaxers,” Rosenberg added. continue reading