Energy Drink Consumption, Gastritis, and Anxiety Disorders: A Narrative Review of the Evidence and Proposed Mechanistic Links

Energy drink (ED) consumption has increased sharply worldwide over the past two decades, particularly among adolescents and young adults. Two health domains have drawn growing clinical attention: gastrointestinal mucosal injury, as documented on upper endoscopy, and psychiatric symptoms, particularly anxiety. This narrative review synthesizes the available evidence linking ED consumption to (1) endoscopic and histologic gastritis and (2) anxiety disorders, and examines the gut-brain axis as a plausible bidirectional mechanism connecting the two. The evidence base consists mainly of case reports, small case series, cross-sectional and longitudinal cohort studies, and animal models; controlled human trials isolating EDs as a discrete exposure are scarce. Caffeine, the dominant pharmacologically active constituent of most EDs, plausibly contributes to both outcomes through distinct but potentially interacting pathways: stimulation of gastric acid secretion and impairment of mucosal defenses on one hand, and antagonism of adenosine A1/A2A receptors with downstream effects on serotonergic and noradrenergic signaling on the other. No existing study has directly quantified a combined triad of ED exposure, endoscopic gastritis, and anxiety disorder within a single cohort, and therefore no pooled effect estimate can be responsibly reported for this specific combination. This review instead maps the separate literatures, highlights converging mechanistic plausibility, and identifies methodological gaps that limit causal inference, including confounding by caffeine from other sources, alcohol co-ingestion, sleep disruption, and reliance on self-reported consumption.