INS and Alzheimer disease: Johnson et al. [31] distinguished 5 steps linking fructose and the occurrence of AD: endogenous fructose is produced in the brain → fructose is metabolized, setting off an innate survival pathway → intracellular uric acid induces neuroinflammation → cerebral insulin resistance and glucose hypometabolism → formation of amyloid plaques and neurofibrillary tangles.