Lycopene, a reddish pigment contained in tomato, belongs to the carotenoid family along with beta-carotene and rutein. This study examined whether administration of lycopene to rats would induce excitation of neurons in the central nervous system. Continuous intake of lycopene-rich food was found to induce accumulation of lycopene in the plasma and liver, and stimulated central neurons in the para-ventricular nucleus, ventromedial nucleus and supraoptic nucleus of the hypothalamus, which are known to be involved in the functions of athrocytosis and water drinking. These findings suggest that lycopene may have some influence on feeding and water-drinking behaviors. (C) 2013 Elsevier Ireland Ltd. All rights reserved.