How are BDNF and blood sugar related?

BDNF (Brain-Derived Neurotrophic Factor) is a protein primarily known for supporting neuronal survival and plasticity. However, emerging evidence links it closely to blood sugar metabolism. BDNF is expressed in insulin-sensitive tissues such as muscle and liver, where it can enhance glucose uptake. Studies show that low BDNF levels are associated with insulin resistance, impaired glucose tolerance, and increased risk of type 2 diabetes. Conversely, physical exercise and certain dietary patterns (e.g., Mediterranean diet) can raise BDNF levels while improving glycemic control. The causal direction remains unclear—low BDNF may be a consequence rather than a cause of metabolic dysfunction. Evidence comes mainly from epidemiological and animal studies; human randomized controlled trials are limited. Thus, the strength of evidence is moderate. For improving blood sugar, established lifestyle interventions (exercise, fiber, weight management) remain primary; BDNF is a promising biomarker but not yet a standalone therapeutic target.