The effect of dietary phytochemicals on nuclear factor erythroid 2-related factor 2 (Nrf2) activation: a systematic review of human intervention trials

Abstract We conducted a systematic review of human trials examining the effects dietary phytochemicals on Nrf2 activation. In accordance with PRISMA guidelines, Medline, Embase and CAB abstracts were searched for articles from inception until March 2020. Studies in adult humans that measured activation (gene or protein expression changes) following ingestion phytochemical, either alone combination included. The study was pre-registered Prospero database (Registration Number: CRD42020176121). Twenty-nine full-texts retrieved reviewed analysis; these, eighteen included review. Most participants healthy, obese type 2 diabetics. Study quality assessed using Cochrane Collaboration Risk Bias Assessment tool. Twelve different compounds examined studies: curcumin, resveratrol sulforaphane most common ( n = 3 each). Approximately half studies reported increases 10); however, many poor had an unclear high risk bias. There is currently limited evidence activate humans. Well controlled intervention are needed to corroborate findings vitro animal studies.