In addition to these properties, recent findings have suggested that green tea may exert its neuroprotective effect through a variety of different mechanisms, including: tea polyphenols inhibiting acetylcholinesterase, which is a target for Alzheimer’s disease medications [26]; green tea extract regulating the secretion of stress hormones such as corticosterone, which is related to cognitive function [27]; and l-theanine modulating serotoninergic [28,29,30], dopaminergic [30], and GABAergic [31] neurotransmission in brain. This evidence concerns the gene ACHE and early-onset autosomal dominant Alzheimer disease.