LEP and metabolic syndrome: From a biological perspective, fat accumulation results in a metabolic imbalance (dyslipidemia, insulin and leptin resistance, gut dysbiosis, hypertension, HPA axis dysregulation) and induces a chronic low-grade inflammatory state, marked by elevated pro- and anti-inflammatory cytokines (e.g., IL-6, TNF), vascular dysfunction, and subsequent neuroinflammation, which can impair brain function and act as a shared biological pathway between metabolic, psychological, and neurocognitive impairment [9,37,90,91,92].