The parabrahial nucleus (PBN) has a key role in appetite suppression, but precisely which neurons mediate this effect is unknown. Carter et al. identified a population of calcitonin gene-related peptide (CGRP)-expressing neurons in mice that project from the PBN to the central nucleus of the amygdala. Using optogenetic and pharmacogenetic approaches, they found that increasing activity in this pathway suppressed appetite, and inhibition increased food intake and prevented starvation in mice in which agouti-related protein (AGRP)-expressing PBN neurons were ablated. Thus, this CGRP circuit has an important role in suppressing appetite.