INS and Alzheimer disease: However, another study found that patients with regular insulin use presented with better memory function after 2 and 4 months compared with patients receiving a placebo (Craft et al., 2017); this is likely because insulin administration increases brain insulin levels and improves memory and cognition in MCI or early stages of AD (Benedict et al., 2011; de la Monte, 2013), which leads to enhanced Aβ clearance from the brain (Reger et al., 2008).