NR1H4 and obesity due to melanocortin 4 receptor deficiency: FXR levels were positively associated with a family history of obesity (p = 0.031), the use of topical agents (p = 0.024), and serum zinc levels (p = 0.025), whereas no significant associations were observed with gender (p = 0.721) or eating behavior scores (cognitive restraint, p = 0.483; uncontrolled eating, p = 0.581; emotional eating, p = 0.814).