PHYSIOLOGICAL EFFECTS OF MEDITATION ON HUMAN PHYSIOLOGY

Meditation is increasingly recognized as a comprehensive mind–body intervention capable of producing significant physiological adaptations across multiple biological systems. This review synthesizes current evidence on the cardiovascular, respiratory, neurophysiological, endocrine, immune, and molecular effects of meditation. Meditation enhances autonomic balance by increasing parasympathetic activity and reducing sympathetic output, resulting in lower heart rate, blood pressure, and improved heart rate variability. Respiratory efficiency improves through decreased respiratory rate and enhanced respiratory sinus arrhythmia. Neurophysiologically, meditation induces increased alpha and theta EEG activity, strengthens functional connectivity, and promotes neuroplastic changes within the prefrontal cortex, hippocampus, anterior cingulate cortex, and limbic structures. Endocrine modulation is evident through reduced cortisol, epinephrine, and norepinephrine levels, along with increased melatonin secretion, reflecting improved stress regulation and circadian stability. Immunologically, meditation enhances natural killer cell activity, elevates immunoglobulin levels, and reduces pro-inflammatory cytokines, thereby strengthening immune resilience. At the molecular level, meditation influences gene expression, upregulates neurotrophic factors, improves oxidative balance, and enhances metabolic regulation. Collectively, these findings demonstrate that meditation promotes systemic homeostasis, cognitive enhancement, emotional resilience, and cellular protection. The review underscores the potential of meditation as a preventive and therapeutic strategy, while emphasizing the need for further longitudinal and mechanistic studies to optimize clinical applications.