Myths vs facts: BDNF and sleep

BDNF (Brain-Derived Neurotrophic Factor) supports neuronal plasticity and survival. A common myth is that BDNF directly controls sleep. Evidence shows that sleep deprivation reduces BDNF levels, while restorative sleep normalizes them, but causality is unclear. Most data come from animal models and small human studies. Genetic variants like Val66Met have weak predictive power for individual sleep traits. Lifestyle factors (exercise, stress reduction) influence BDNF more robustly. Direct-to-consumer tests claiming to predict sleep quality via BDNF are not clinically validated. Bottom line: BDNF is a biomarker, not a sleep gene. Improving sleep hygiene and physical activity are evidence-based strategies.