Relevant to the present study, the levels of lactate in the cerebrospinal fluid (CSF) of AD patients has been reported to be elevated [5] and one of the enzymes critical to the production of Aβ peptides, β-amyloid cleaving enzyme (BACE1), is strongly influenced by pH, with an optimal pH well below 6.0 [6]. Here, BACE1 is linked to Alzheimer disease.