Vitamin C comes from fresh vegetables and fruits and is not easily deficient with a proper diet. If a deficiency is confirmed in your body, you should follow the advice of your doctor and take reasonable supplements. Vitamin C is good for promoting substance metabolism and enhancing the utilization of iron and carbohydrates, as well as reducing capillary functionality, which is beneficial for blood clotting and also enhances resistance to external pathogenic infections. It is also often used clinically as an adjunct to the treatment of chronic iron toxicity, acute and chronic infections, purpura and other diseases. But if you insist on taking it for a year without medical advice or take too much vitamin C, it may cause the following adverse consequences: 1, gastrointestinal dysfunction: vitamin C will stimulate gastric juice secretion, long-term excessive secretion of gastric juice will lead to gastrointestinal dysfunction, which will increase the occurrence of various diseases such as gastritis and gastric ulcer; 2, urinary tract stones: excessive intake of vitamin C will lead to an increase in the level of oxalic acid in the body, a large amount of oxalic acid and calcium elements Combined with calcium elements to form oxalate, accumulate in the urethra, easy to induce urethral stones; 3, affect the bones: the right amount of vitamin C can help promote the development of children’s bones and teeth, but too much vitamin C may affect the healthy development of bones; 4, affect the development of the fetus: women during pregnancy intake of too much vitamin C, will affect the development of reproductive cells, which will affect the healthy growth of the fetus in the body, and in serious cases It may even increase the chance of congenital scurvy or miscarriage; 5, other: long-term vitamin C patients in the sudden discontinuation of the drug, the body will still maintain a high metabolic function, which may lead to bleeding gums, loss of appetite, rash and other symptoms of vitamin C deficiency, which can seriously induce scurvy. Generally, the daily intake of fresh fruits and vegetables can meet the vitamin C content required by the body, so it is recommended that people without obvious symptoms of vitamin C deficiency should not take the drug without permission.