Although feeding a high-fat diet caused severe memory deficit in APP Tg with NSY background (Nagoya-Shibata-Yasuda) mice, which are established as an inbred animal model with spontaneous development of diabetes (Shibata and Yasuda, 1980; Ueda et al., 2000), we observed no increase in brain Aβ load by a high-fat diet (Takeda et al., 2010b). Here, APP is linked to diabetes mellitus.