It has been proposed that in patients with AD, alteration of the lipid profile and the consequent appearance of metabolic syndrome, especially in childhood, may be a consequence of 25 OH vitamin D deficiency due to insufficient serum levels, receptor (VDR) hypofunction, or dysregulation of enzymes involved in its metabolism (CYP24A1) [16,19-21]. Here, CYP24A1 is linked to Alzheimer disease.