婴幼儿在生长发育的过程中,每个年龄阶段都有着各自不同的特点,无论是在形体上还是在功能上都有很大的变化。年龄愈小,其生长发育就愈快,所需的各种营养物质就更应及时地补充。现代医学证明,小儿在生长发育阶段,每日需要摄入的营养物质按单位体重计算要比成人多得多。儿童营养学家认为,影响我国儿童正常发育的主要问题是膳食结构不合理,主要表现在蛋白质、脂肪、碳水化合物三者的摄入量不平衡.另一个主要因素则是某些维生素的摄入量不足。维生素是维持机体正常代谢和机能所必需的一类营养素.大多数维生素人体自身不能合成,必须从食物中获取,虽然人体对它的需要量甚微,但其作用十分重要,它量维持儿童生长及调节正常生理功能所必需的,缺少任何一种维生素都有可能发生疾病。例如:维生素 A 可维持正常的视觉,减少呼吸道感染和腹泻的发病率;维生素 B 是维持体内代谢及生长所必需.如果缺少 B 族维生素会发生脚气病,发生新生儿抽搐及营养性巨细胞贫血等,还会出现消化,神经及心脏各方 Infants and young children in their growth and development process, each age has its own different characteristics, both in physical and function have great changes. The younger, the faster growth and development, the required variety of nutrients should be more timely replenishment. Modern medicine proves that children in the growth stage, the daily intake of nutrients per unit weight more than adults. Children nutritionists believe that the main problem affecting the normal development of children in our country is the unreasonable diet structure, which is mainly imbalanced in the intake of protein, fat and carbohydrates, and the other main factor is the intake of certain vitamins Insufficient amount. Vitamins are a type of nutrients necessary to maintain the body’s normal metabolism and function.Most of vitamins can not be synthesized by the body itself, must be obtained from food, although its body needs little, but its role is very important, it maintains the growth of children And the regulation of normal physiological functions necessary, the lack of any one kind of vitamins are likely to occur disease. For example: Vitamin A can maintain normal vision, reduce the incidence of respiratory tract infections and diarrhea; Vitamin B is necessary to maintain metabolism and growth in the body. If the lack of B vitamins can cause beriberi, neonatal convulsions and nutritional giant cell anemia And so on, there will be digestion, nerves and heart parties