Intranasal insulin has been shown to improve cognition and/or memory in healthy persons (Benedict et al., 2004, 2007), obese men (Hallschmid et al., 2008), and additionally lower cerebrospinal fluid levels of AB42 in adults with amnestic MCI or mild to moderate AD (Reger et al., 2008; Craft et al., 2012). This evidence concerns the gene INS and Alzheimer disease.