Researchers used data from the Black Women's Health Study, which has followed 59,000 African American women since 1995.
African American women who have two or more children face a much higher risk of developing an aggressive form of breast cancer than those with no kids.
From the Globe:
[The] study led by Julie Palmer, senior epidemiologist for Slone Epidemiology Center at Boston University, found that breast-feeding may mitigate that risk. African-American women who had two or more children and breast-fed had no more risk of the cancer than those who had no children. One theory is that breast-feeding allows the breast to return more slowly to its normal structure after childbirth.
Palmer says that encouraging African American women to breastfeed might lower the cancer rate.
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