Vitamin A deficiency remains a major public health problem in developing country worldwide. Young Children are considered to be at greatest risk of deficiency. However, there is little information on the vitamin A requirement of Chinese children. In the present study, about 400 children aged between 4 and 9 years old in a kindergarten and an elementary school of Shiyan City were screened before admission by questionnaire and anthropometric measurement. The vitamin A status of children was assessed by serum vitamin A level, relative dosage reaction and stable-isotope dilution technique. At the same time, their dietary vitamin A intakes were estimated by weighted-food dietary survey. The dietary vitamin A requirement in young children was determined on the basis of dietary vitamin A intakes in Children with adequate vitamin A level.

Inclusion Criteria:

• well-nourished children with normal serum retinol(>=1.40umol/L)

Exclusion Criteria:

• ongoing or previous illnesses,
• having taken nutritional supplements within 3 months,
• positive results in the fat absorption test or parasite test,
• increased level of CRP (> 8 mg/L), or
• lower serum level of retinol (< 1.40 umol/L)

The study was carried out in a kindergarten and an elementary school in Shiyan city, Hubei province of China. Initially, 201 kindergarten children (4-6 years old) and 202 grade children (7-9 years old) were subjected to a questionnaire survey on personal information, medical history and dietary habits including dietary supplements.ongoing or previous illnesses, having taken nutritional supplements within 3 months, positive results in the fat absorption test or parasite test, increased level of CRP (> 8 mg/L), or lower serum level of retinol (<1.40 umol/L), and higher ratio in relative dosage reaction test(>20%) .After the screening, 123 children were selected and completed the study, but 60 subjects were randomly selected for the DRD test to evaluate liver vitamin A storage.