Prevalence and Risk Factors of Iron Deficiency and Iron Deficiency Anemia in Preschool Children of China: A Prospective Observational Study.

To explore the prevalence and risk factors of iron deficiency (ID) and iron deficiency anemia (IDA) in preschool children. A total of 3503 preschool children (3-4 years) who have normal physical checkups for kindergarten admission have been studied. The prevalence of children's ID and IDA has been detected, and the main influencing factors of children's ID and IDA were analyzed by factor comparison and logistic regression. The prevalence of ID and IDA was 25.4% and 7.5%, respectively, in the total of 3503 children. Male gender, exclusive breastfeeding, delay of solid food supplement, picky eating, recent respiratory infection and diarrhea, and parents without a bachelor's degree or above or other places' household registration are associated with children's ID and IDA. Among these, male gender, exclusive breastfeeding, not adding food in time (such as > 6 months after birth), and picky eating are the independent risk factors for children's ID and IDA. The prevalence of children's ID and IDA is still at a high level. Among 3-4 years preschool children, boys are at a higher risk of developing ID and IDA. Feeding-related factors, including exclusive breastfeeding and picky eating habits, are particularly important for the occurrence of ID. Consequently, it is necessary to conduct further investigations and research on different age groups in various regions.