It turns out that you don't need to worry about hair-straightening chemicals leading to breast cancer. That's the news from a study published recently by researchers at Boston University and Howard University in the journal Cancer Epidemiology, Biomarkers & Prevention.
According to the study, which followed more than 48,000 women who participated in the Black Women's Health Study, chemical relaxers used to straighten hair were not associated with an increased risk of developing breast cancer among African-American women.
Neither did the researchers find any increases in breast cancer risk due to the type of hair relaxer used or the frequency and duration of use. The investigation found those women who used relaxers 7 or more times a year over a 20-year span or longer had the same risk of breast cancer as those who had used the chemicals for less than a year.
This is indeed good news for women who use these products but who worried about their breast cancer risk. One caveat, however: Because hair relaxers can enter the body through cuts or lesions in the scalp and because these products are not fully monitored by the Food and Drug Administration, they may still contain potentially harmful compounds.
The researchers explain that manufacturers of hair relaxers and hair dyes are not required to list all the ingredients used in their products because they are considered trade secrets.
The study found that younger women used hair relaxers more often than older women did. The scientists also discovered that the majority of women start using hair relaxers before age 20 and one-third of them used the chemicals at least 7 times a year.
But when the researchers examined the association between use of hair relaxers and breast cancer incidence (based on 574 newly diagnosed cases of breast cancer identified during the follow-up period), they found no connection between their use of relaxers and increased breast cancer risk, either overall or among the younger women, even if use had been frequent and of long duration.
But all African-American women still need to bear in mind that breast cancer incidence is higher among black women ages 40 or younger than among white women of the same age. This increased risk has not been fully explained by known risk factors such as race and family history. At all ages, African-American women are more likely to die of breast cancer than are white women.
So, ladies, you can now worry less about the effect of hair-straightening chemicals on your breast health — but do get your mammograms anyway.