Drinking too much functional drinks will have certain harmful effects, such as may lead to dental caries and obesity, may also lead to malnutrition and affect the quality of sleep and so on. 1. Dental caries: functional drinks contain sugar and other acidic substances are usually more, if you often drink too much, it is easy to erode the teeth, soften the tooth enamel, thus leading to dental caries. 2. Obesity: functional drinks contain more sugar, if you often drink too much, the body can not be digested in a timely manner, too much sugar is easily converted to fat accumulation in the body, leading to obesity. 3. Malnutrition: Functional drinks contain more sugar and less other nutrients, if you often drink too much, it will affect the intake of other foods, thus leading to malnutrition. 4. Impact on sleep: Functional drinks usually contain caffeine, if often consumed too much, it is easy to lead to central nervous system excitation, thus affecting the quality of sleep. For the sake of health, it is recommended to drink as little or no functional drinks as possible, and at the same time, pay attention to balanced nutrition, do not pick food.