LEP and mood disorder: Notwithstanding this, leptin has multiple roles in glucose homeostasis, including improving insulin sensitivity,146 which, as noted above, has been shown to be important in treating bipolar depression.93,94 LC/KD reduces leptin while also improving sensitivity to leptin.150 The role of ghrelin in mood disorders is unclear,147 but ketosis rapidly suppresses ghrelin, reducing appetite within a few days.102