维生素可分为水溶性和脂溶性两种,脂溶性维生素如维生素 A、维生素 D等摄人过多时,不能通过尿液直接排出体外,易在体内大量蓄积,引起中毒。如果长期口服大量维生素 D,可导致高血钙症、厌食、恶心、呕吐、弥散性肌肉乏力、肌肉疼痛等。水溶性维生素多吃后虽可以从尿中排出,毒性较小,但大量服用仍可损伤人体器官,如大剂量服用维生素 C,可能刺激胃黏膜出血。此外,长期过量服用维生素,可使机体对食物中的维生素吸收率降低,一旦停服,会导致维生素缺乏的症状。实际上,只要合理饮食,常吃蔬菜、水果,一般不会造成人体维生素缺乏。只有一些特殊人群容易缺乏维生素,需要有针对性的适当补充。比如孕妇及哺乳妇女因胎儿和乳儿的额外需要,易出现维生素 A、D 和 C 的缺乏,应多吃些瘦肉、肝、蛋、鱼类、新鲜 Vitamins can be divided into two kinds of water-soluble and fat-soluble, fat-soluble vitamins such as vitamin A, vitamin D intake too much, can not be directly excreted through the urine, easy to accumulate in the body, causing poisoning. If long-term oral large amounts of vitamin D, can lead to hypercalcemia, anorexia, nausea, vomiting, diffuse muscular fatigue, muscle pain and so on. Although water-soluble vitamins can be eaten from the urine after eating, less toxic, but taking large quantities can still damage human organs, such as taking large doses of vitamin C, may stimulate gastric mucosal bleeding. In addition, long-term excessive intake of vitamins, can make the body reduce the absorption of vitamins in food, once stopped, can lead to vitamin deficiency symptoms. In fact, as long as a reasonable diet, eat vegetables, fruits, generally do not cause the body lack of vitamins. Only some special populations are easily lack of vitamins, need appropriate supplements targeted. For example, pregnant women and lactating women due to the extra needs of fetuses and infants, prone to the lack of vitamin A, D and C, should eat more lean meat, liver, eggs, fish, fresh