High‐density lipoprotein (HDL), as a crucial component of lipid metabolism, have roles in regulating Alzheimer's disease (AD) core pathology amyloid β (Aβ) and phosphorylated tau (p‐tau) through its apolipoproteins, which are associated with brain structures, cognition, and risk of dementia. This evidence concerns the gene MAPT and early-onset autosomal dominant Alzheimer disease.