The Link Between BMI and Breast Cancer

Before menopause, a higher BMI seems to be protective against breast cancer
Shutterstock 710369335
Photo by Sk Elena/

A recent study published in JAMA Oncology explores the relationship between body mass index and breast cancer, which is the most commonly diagnosed type of cancer in women in the U.S. It also affects younger women more often than other types of cancer. The researchers hope that the study results will lead to a better understanding of the mechanisms and risk factors involved.

Scientists from the Institute of Cancer Research in London combined data from 19 studies. The data includes 758,592 premenopausal women and, among them, 13,082 new cases of breast cancer were diagnosed across an average follow-up period of nine years.

A number of risk factors for breast cancer are now known, and one of these is adiposity. This is the amount of fat an individual carries on his or her body.

However, the influence of adiposity — as measured by body mass index — is not as clear-cut.

Before women go through menopause, a higher BMI seems to be protective against breast cancer, and the opposite is true after menopause, at which point a higher BMI starts to increase the risk of breast cancer. Researchers hope that further study on this subject will provide more information on the criteria for risk of the disease.

Learn more at


Categories: Exercise, Health