Does being overweight but not obese increase women’s breast cancer risk?
A number of studies have demonstrated that there is a progressive increase in breast cancer risk with BMI. This indicates that being overweight is associated with increased breast cancer risk. However, the level of risk associated with overweight is less than that associated with obesity. What is the biological explanation for the relationship between obesity and postmenopausal breast cancer risk? The biological relationship between obesity and breast cancer risk is not clearly understood but a number of hypotheses have been proposed. Three of the major hypotheses are discussed below. 1) Obesity leads to a larger exposure to estrogen. It is well established that the amount of estrogen in the body and the length of lifetime exposure to estrogen is linked to breast cancer risk. Women who are exposed to more estrogen due to a longer period of reproductive capacity or who have higher levels of naturally produced estrogen within their bodies are at higher risk of getting breast cancer. Stud
