Weight loss and browning effects of FGF21 persist in obesity as DIO male mice treated daily with FGF21 (1 mg/kg) for 2 weeks experience a 20% reduction in body weight without affecting food intake, and upregulated gene expression of Pgc-1α, and Ucp1 in WAT and BAT compared to controls [76]. This evidence concerns the gene UCP1 and obesity due to melanocortin 4 receptor deficiency.