According to study published in medical journal JAMA Oncology, post-menopausal women that have excess body fat are at a greater risk of breast cancer. Dr. Andrew Dannenberg, one of the study’s authors who is also the director of cancer prevention and Sandra and Edward Meyer Cancer Center, women with excess body fat who are in post-menopausal stage have double the risk of contracting estrogen-dependent breast cancer. Even women that have normal body mass index could develop these estrogen dependent cancers which are referred to as ER-positive in medical parlance. This type of cancer occurs when receptor proteins or cells attach themselves to the estrogen hormone and depend on it to grow.
The research was carried out on American women between ages of 50 and 79 years numbering around 3460 that were in menopausal stage. This study group was part of Women’s Health Initiative and their body composition was measured during beginning of the program. Dannenberg stated that 146 women out of this study group developed breast cancer which was ER-positive forcing researchers to find a relationship between excess fat and this cancer. They discovered that increase of 11 pounds in fat mass of the body is associated with 35 %and 5 kg increase in trunk mass led to 56 % increase risk in ER positive breast cancer.
The study also discovered that invasive breast cancer where the disease has spread to surrounding breast tissue, an increase of 5 kilogram in whole body fat mass increased risk by 28 % while increase in trunk fat of same amount led to risk of 46 %. Dannenberg said that this study showed how women with even normal body mass index could be at risk of breast cancer. The strength of this research is analysis of location of fat levels in the body that increase risk of the disease enabling people to take better care of their bodies.