Fatigue is a very non-specific symptom and could occur due to stress/ anxiety, inappropriate diet, low
blood sugar, low
blood pressure, micronutrient deficiencies, anemia, hormonal/ endocrine abnormalities/ metabolic disorders, primary neuro-muscular causes, sleep disorders, systemic causes such as infections/ inflammations, electrolyte abnormalities, a few auto-immune, side effect of a few medications/ drugs etc.