Myths vs facts: BDNF and gut health

BDNF (Brain-Derived Neurotrophic Factor) is a protein critical for neuronal survival and plasticity. The link to gut health is often explained via the gut–brain axis: gut microbes produce short-chain fatty acids and other metabolites that may modulate BDNF expression. **Myth:** You can directly boost brain BDNF by taking specific supplements or 'superfoods'. **Fact:** Evidence is mostly mechanistic (animal studies, cell models). In humans, regular exercise and a fiber-rich diet (e.g., Mediterranean) are associated with higher BDNF levels, but a direct causal role of the gut microbiome is not firmly established. **Limitations:** Blood BDNF does not perfectly reflect brain BDNF. Many confounders (stress, sleep, genetics) affect levels. Consumer tests like MyBody-X for BDNF or gut–brain axis are not validated; their predictive value is low. For clinical concerns, consult a healthcare professional.