An analysis co-led led by UNC Lineberger's Hazel B. Nichols, PhD, linked higher body mass index to lower breast cancer risk for younger women, even for women within a normal weight range.
While obesity has been shown to increase breast cancer risk in postmenopausal women, a large-scale study co-led by a University of North Carolina Lineberger Comprehensive Cancer Center researcher found the opposite was true for premenopausal women: higher body fat was linked to lower breast cancer risk.
The findings, published in the journal JAMA Oncology, show the need to better understand breast cancer risk factors in younger women before menopause, said UNC Lineberger's Hazel B. Nichols, PhD.
"The drivers of breast cancer risk can be different for young women compared to older women, so we need to do a better job of understanding what contributes specifically to breast cancer risk in younger women so we can make appropriate recommendations for them," said Nichols, who is an assistant professor in the UNC Gillings School of Global Public Health. "This study is not a reason to try to gain weight to prevent breast cancer. Heavier women have a lower overall risk of breast cancer before menopause, but there are a lot of other benefits to managing a healthy weight that should be considered. What it does do is help us to try to understand what contributes to breast cancer risk in younger women."