剑桥词典one of the vitamin B complex found in foods such as wheat , beef , chicken , and milk , important for producing energy from food and for keeping the digestion and nervous system healthy 烟酸（在小麦、牛肉、鸡肉和牛奶等食品中含有的一种复合维生素B，对体内能量转化和保持消化、神经系统健康有着重要作用） 返回 niacin