Obesity resistant rats have greater orexin receptor gene expression and orexin behavioral sensitivity (Perez‐Leighton et al., 2012; Teske et al., 2006; Teske et al., 2008); are more physically active; and have consolidated sleep (Mavanji et al., 2010; Teske et al., 2006), indicating a protective effect of orexin against obesity. Here, HCRT is linked to obesity due to melanocortin 4 receptor deficiency.