Bisphenol A (BPA), a commonly used plastic additive, is believed to cause obesity. As an environmental endocrine disruptor, BPA is closely associated with the onset and progression of BC. However, the molecular mechanisms underlying the promotion of breast cancer by BPA remain unclear. As obesity is a significant risk factor for breast cancer, this study aimed at exploring whether BPA facilitates the progression of breast cancer by inducing obesity. Using the National Health and Nutrition Examination Survey data, a positive correlation was observed between BPA exposure and the risk of sex-specific cancers among US adults with body mass index ≥30, suggesting that obesity may be influenced by urinary BPA. 3T3-L1 cells differentiated into mature adipocytes following treatment with 10