Machado , et al. - In this cross-sectional clinical study, researchers assessed postmenopausal women with breast cancer (BC) women vs postmenopausal women without BC for the rate of and risk factors for low pretreatment vitamin D (VitD) levels. Researchers enrolled 209 women with BC (case group) and 418 women without BC (control group) with an age range of 45 to 75 years. A higher body mass index and a higher percentage of obesity were noted in the BC group vs the control group (57.4% vs 40.2%). They observed an increased risk of VitD deficiency at BC diagnosis in postmenopausal women, which was linked with a higher rate of obesity, vs women of the same age group without cancer.