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Unravelling the role of brain-derived neurotrophic factor (BDNF) in anorexia, bulimia, and binge-eating disorder: A systematic review and meta-analysis

Fioranelli M, Sedati P, Topa A, Roccia MG, Santoni G, Garo ML

Journal of psychosomatic research, 2026

17 participants · 2 citations

Abstract

Background: Brain-derived neurotrophic factor (BDNF) plays a role in neuroplasticity, appetite regulation, and reward processing. Its possible involvement in eating disorders (EDs) has been investigated; however, contradictory findings and substantial methodological heterogeneity have prevented definitive conclusions.

Objective: To systematically evaluate peripheral BDNF levels in individuals with EDs, healthy controls and recovered individuals.

Methods: A systematic review with meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement (CRD420250654199). Observational studies and randomized controlled trials comparing BDNF levels in individuals with and without EDs were included. The Newcastle-Ottawa Scale and risk-of-bias tool for randomized trials were used.

Results: Twenty-one studies were included. BDNF serum levels were significantly lower in acute anorexia (AN) compared with healthy controls (Standardized Mean Difference [SMD] = -0.49;p < 0.001,n = 17), with significance maintained after excluding outliers (SMD = -0.41; p < 0.001,n = 8). No significant difference was found between recovered AN and controls. Bulimia nervosa (BN) individuals showed significantly lower BDNF serum levels (SMD = -0.72;p < 0.001,n = 4). Longitudinal studies showed a significant increase in serum BDNF levels after recovery (SMD = 1.78;p = 0.003,n = 6).

Discussion: These findings support a predominantly state-related…

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Evidence Hub reads this as a meta-analysis, done in people. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid. Reported size: 17 participants or records.

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