Estimate of breast cancer risk reduction with weight loss.

Upper body fat localization has been associated with an increased risk of cancer. This study demonstrated that 64.2% of 124 women with at least a 4.5-kg weight loss decreased their upper body fat localization, as measured by a reduction in their suprailiac-thigh skin fold ratio and other skin fold thicknesses associated with upper body fat localization. Based on a risk model previously developed for breast cancer and upper body fat localization, a reduction in estimated breast cancer relative risk of 45% was calculated for the entire group of women who lost 4.5 kg or more in weight. Greater weight loss further reduced upper body fat localization and estimated breast cancer risk based on this model.