BDNF and psychiatric disorder: While BDNF Val66Met has been implicated as a genetic risk factor in several psychiatric disorders (e.g. schizophrenia, psychosis, major depression, anxiety, and eating disorders), cognitive compromised disorders (e.g. AD and PD) and metabolic syndrome [13–15], very little data are available on its association with metabolic risks in general population, especially in long-lived individuals with good cognitive function.