NAC blocked fat mass and the development of obesity reducing HFD-induced macrophage infiltration, and enhanced adiponectin gene expression. NAC oral administration suppressed hepatic lipid accumulation, as evidenced by lower levels of triglyceride and cholesterol in the liver. The beneficial effects are associated with a decrease in hepatic peroxisome proliferator-activated receptor (PPAR)γ and its target gene expression. The gene discussed is ADIPOQ; the disease is obesity due to melanocortin 4 receptor deficiency.