Recent reports demonstrate that acute access to HFD rapidly alters the activity of hypothalamic AgRP neurons, resulting in a de‐valuation of the regular chow diet, such that acute anorexia develops when animals are switched back from an HFD to a regular chow diet (Beutler et al., 2020; Mazzone et al., 2020). The gene discussed is AGRP; the disease is Anorexia.