The goals of this study were to use the obese breast cancer model to investigate (1) the long-term effects of obesity and DHEA treatment on body weight gain and liver steatosis and (2) the effects of long-term obesity and DHEA on serum IGF-1, IGFBP-3, DHEA, and DHEA-S. Here, IGF1 is linked to obesity due to melanocortin 4 receptor deficiency.