Investigation Of Serum 25-OHD Status In Infants With Different VD Prevention Doses

Objective: By measuring the serum 25 OHD level of children aged 0-3years,we aim to detect the vitamin D nutritional status and its influencing factors of infants with different VD prevention in Chongqing,and provide a basis for rational supplementation of VDMethods: Five hospitals in different economic levels in Chongqing were selected to perform normal physical examination of infants.According to the inclusion and exclusion criteria,751 healthy children aged0-3 years were surveyed,and the serum 25 OHD concentration was determined by high performance liquid chromatography-mass spectrometry(LC-MS).The differences of 25 OHD were studied according to different VD prevention doses,and multivariate analysis of variance was performed.Results: The VD supplement rate of infants aged 0-3 years was 74.6%(560/751),and the VD preventive supplement dose ranged from30IU-1600 IU per day;The average level of serum 25 OHD was35.29±10.39ng/ml.With the increase of vitamin D supplementation dose,serum 25 OHD increased first and then stabilized.The serum 25 OHD level(30.51±11.03 ng/ml)in the unsupplemented group was significantly lower than that in each supplement group;Season,age,feeding method,and different preventive doses can independently affect serum 25 OHD levels.Different seasons,feeding methods and preventive doses can affect serum 25 OHD levels interactively.In children with no food source in winter and spring,the serum 25 OHD level was the lowest(18.44±11.91ng/ml);The VD insufficiency and deficiency rate in the unsupplemented group was 14.7%,which was significantly higher than that in each supplement group(P<0.05).Conclusion: 1.The prevalence of prophylactic VD in infants aged 0-3years in Chongqing is high,but there is still a large dose difference in VD preventive supplementation.2.Preventive vitamin D supplementation is an important measure to maintain serum 25 OHD levels in infants and young children.Seasons and feeding methods can significantly affect the nutritional status of VD.3.The recommended dose of VD for infants is400 IU per day.