A study published in the journal JAMA Oncology has proven that young women with high body fat have a decreased chance of developing breast cancer before menopause.
Dale Sandler, the paper’s co-senior author who is also the head of the Epidemiology Branch at the National Institute of Environmental Health Sciences (NIEHS), said: “It is well known that women who gain weight, particularly after menopause, carry an increased risk of postmenopausal breast cancer.
“Our finding that breast cancer risk is not increased in obese premenopausal women, and in fact decreases, points to the possibility that different biologic mechanisms are responsible for causing breast cancer
in younger women.”
The researchers came to this conclusion after analyzing data from 19 different studies, comprising 758,592 women from around the world.
The participants ranged in age from 18 to 54 at the beginning of study. The study evaluated the risk of developing breast cancer in relation to Body Mass
Index (BMI) within different age brackets.
According to the study, the strongest effect was seen in relation to BMI at ages 18 to 24, with very obese women in this age group being 4.2 times less likely to develop premenopausal breast cancer compared to women with low BMI at the same age.
However, Sandler and her colleagues are unsure why young, premenopausal women with a high BMI appear to be protected against breast cancer. She cautioned that young women should not intentionally gain weight to lower their
breast cancer risk.
“There are so many health risks associated with being overweight or obese.
“We still believe it is important for women to maintain a healthy weight throughout life,” Sandler said.