In fact, dieting at the beginning of weight loss has a little effect, but if excessive dieting is actually a lot of harm, mainly the following points: 1, excessive dieting can easily lead to nutritional imbalance, may cause protein, vitamins and minerals intake is insufficient, long-term dieting in this way, and may even affect the normal immune function; 2, long-term excessive dieting, but also lead to a decline in the body’s basal metabolic rate. Because the body consumption is divided into three major parts: basal metabolism, physical activity and the special thermal effect of food, of which basal metabolism accounts for 60%-70% of energy consumption, which is the majority. Excessive dieting, the body will start the protection mechanism, is the energy reserves into the conservation mode, is to eat a little more to help you reserve up and will not help you consume, so the basal metabolic rate decreases, a little something to help you store as fat, so it is easy to re-obese, so many fat people often have a low basal metabolic rate, so excessive dieting is not recommended.