Metabolism refers to the body’s basal metabolism, which is calculated using a different formula for men and women; for women it is calculated as 65.1 + 9.6 x weight (kg) + 1.8 x height (cm) – 4.7 x age (years). In contrast, men’s basal metabolic rate is calculated as 66.5 + 13.7 x body weight (kg) + 5.0 x height (cm) – 6.8 x age (years). The heat energy consumed by the human body to maintain basic life activities and carry out metabolism in a fasting, awake and quiet non-stressful state and in a suitable temperature (18℃ to 25℃) environment is called basal energy expenditure. The heat energy consumed per 1m² of body surface area per unit of time to maintain basal metabolism is called basal metabolic rate. Normally, adult males consume about 4.2kJ (lkcal) per kilogram of body weight per hour, i.e., the daily energy requirement is 1,500-1,800kcal; the basal metabolic rate of adult females is lower than that of adult males by 2%-12%; the elderly is lower than that of the middle-aged people by 10%-15%; and the children are higher than that of the adults by 10%-12%. If the basal metabolism appears to be elevated or lowered, it is necessary to consult a doctor for a clear diagnosis in order to prevent missing the best time for treatment.