我们都知道母乳是婴儿最好的食物。母乳中非蛋白氮约占总氮的25%，核苷酸总量占非蛋白氮的2%～5%[1]。核苷酸是核酸（nucleic acid）的基本组成单位，由碱基、五碳糖和磷酸构成。其中碱基是含氮的杂环化合物，包括嘌呤和嘧啶。五碳糖有核糖和脱氧核糖之分。碱基与五碳糖通过缩合反应形成核苷，核苷再与磷酸反应，脱水后形成磷脂键，生成核苷酸。除了构成核酸之外，在人体内，核苷酸还以其他衍生物的形式存在，参与各种物质代谢及功能调节活动，例如核苷酸是细胞内化学能的载体，如三磷酸腺苷（adenosine triphosphate，ATP）、三磷酸鸟苷（guanosine triphosphate，GTP），还能形成细胞信号转导过程中的第二信使（环腺苷酸、环鸟苷酸），以及形成各类辅酶等。
人体内的核苷酸主要由机体细胞合成，食物并不是主要来源，因此核苷酸的功效及机制研究不被重视。然而核苷酸对机体中生长代谢速度较快的免疫系统细胞、骨髓细胞、肠黏膜细胞等，以及机体在应激、创伤状态下非常重要[2-4]。研究还发现，对于早产儿、小于胎龄儿、坏死性小肠结肠炎患儿等，额外补充核苷酸，对于追赶生长以及疾病恢复有显著的帮助[5，6]。
临床研究发现婴儿配方奶粉添加核苷酸有多种优势，包括免疫、肠道健康、睡眠、代谢健康和体格生长。
重点来了，中国宝宝补充核苷酸要认准中国妈妈乳汁中的核苷酸比例，目前只有伊利金领冠研究并独家专利保护中国母乳的核苷酸比例，用于产品，大家一定要认准品牌和营养标签，支持我们的国货和有价值的中国发明专利。
参考文献：
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