HCAR2 and colorectal carcinoma: In a recent article published in Nature, Dmitrieva-Posocco et al.1 showed that ketogenic diets (KD) exert strong abilities to prevent and treat colorectal cancer (CRC) via the ketone body β-hydroxybutyrate (BHB)-mediated hydroxyl-carboxylic receptor.2 (Hcar2)-homeobox only protein homeobox (Hopx) signaling axis in multiple in vivo and in vitro models (Fig. 1).