Vitamin c is called ascorbic acid. As a water-soluble vitamin, its main function is to reduce the harm of free radicals to the body by resisting the oxidation of human nuclear plasma. Vitamin C is also involved in the synthesis of collagen in organs including bones and skin. If vitamin C is deficient, it may cause bleeding and even visceral bleeding. Vitamin c itself cannot be synthesized in the body and must be supplemented by food every day. The recommended daily intake of vitamin C for adults is 60- 100 mg. Liu Yang, a researcher at the Institute of Agricultural Products Processing, Chinese Academy of Agricultural Sciences, believes that the content of vitamin C in vitamin C drinks on the market is between 25 and 50 mg per100 ml, and most of them are above 40 mg/100 ml. Calculated by 500ml per bottle, the content of vitamin C in each bottle is 200mg, which is much higher than the recommended intake for adults. At the same time, he believes that vitamin C drinks generally have high sugar content, and drinking in large quantities will lead to excessive sugar intake and energy intake. At the same time, most vitamin C drinks contain preservatives, pigments, antioxidants, pectin, vitamins, flavors, sweeteners, etc. These are not the nutrients needed by the human body. Liu Yang reminded that vitamin C drinks also contain elements such as sodium. Excessive intake of vitamin C will increase the burden on the heart and lead to an increase in blood pressure. Zhangqian, deputy chief physician of Nutrition Department of Tongren Hospital, opposes all drinks. He said, "No matter what concept is adopted to package this product, no matter how attractive the appearance and advertisement are, it is unnecessary. Vitamin C is a water-soluble vitamin. We can satisfy our needs by eating fresh fruits and vegetables. Excessive intake of vitamin c is unnecessary. In addition, long-term large intake will cause dependence. Once the dose is reduced, it may cause visceral bleeding, gingival bleeding, skin spots and other symptoms. Of course, the above situation is a more extreme example. " Li Ning, the chief physician of the Nutrition Department of Peking Union Medical College Hospital, also does not advocate drinking vitamin C drinks: "Because drinks contain sugar, eating too much sugar is not only bad for the human body, but also causes obesity and has certain risks for diabetes. Therefore, people with obesity, diabetes, hypertension, cardiovascular and cerebrovascular diseases should pay attention to drinking less such drinks. " Drinking vitamin c drinks can't beautify people. Many people choose vitamin C drinks because their slogan is "health and beauty". In this regard, Professor Bao Ping from the College of Food Science and Nutritional Engineering of China Agricultural University thinks: "Vitamin C drinks have no effect on beauty, so it is better to drink water. In our daily life, we should eat some natural fruits and vegetables. The vitamin C we supplement from food is much better than that obtained by drinking this drink. " People's complexion is closely related to their physical condition. Protein, fat and carbohydrates determine the main aspects of physical fitness, and then minerals and vitamins play a role in regulating energy metabolism, but they do not play a decisive role. Vitamin c has antioxidant effect, which can prevent cancer and resist aging, but it is not shown on the face. The synergistic effect of vitamin C in fruit and other substances will have this effect. "zhangqian said. Relevant data show that in 2005, the detection rates of overweight and obesity among urban men aged 7-22 in China were 13.25% and 1 1.39% respectively. The detection rates of overweight and obesity among urban women aged 7-22 also reached 8.72% and 5.0 1% respectively. Zhangqian believes that lack of exercise is a cause of overweight and obesity, and eating junk food and various drinks is also an important reason. Studies that cannot replace vegetables and fruits show that eating more vegetables and fruits can reduce the incidence of cancer, heart disease and diabetes, but "there is no evidence that drinking vitamin C drinks can replace vegetables and fruits and have the same effect." Liu Yang said. Liu Yang made it clear that the vitamin C needed by human body depends on daily intake of fruits and vegetables, followed by fruit juice and vegetable juice, and finally vitamin C drinks. Eating vegetables and fruits can also supplement other nutrients, such as other kinds of vitamins, flavonoids, carotene, anthocyanins, dietary fiber, potassium and magnesium. These nutrients cooperate with vitamin C to make the human body grow healthily. He believes that for fruits with high vitamin C content, such as kiwifruit, citrus and persimmon, eating one or two a day can meet the human body's demand for vitamin C, such as green pepper, red pepper, cauliflower, bitter gourd and tomato. It also contains a lot of vitamin C. Eating more than 200 grams of vegetables every day can also meet the human body's demand for vitamin C. "Fruits are rich in dietary fiber, and insoluble and soluble dietary fiber can promote people's health, which is impossible for vitamin C drinks." Zhangqian said. Ji Baoping suggested: "In the process of choosing drinks, you can try to choose drinks with less additives and low sugar, such as some pure juice drinks. "