Abstract
Ying Yang Bao (YYB) is conventionally prescribed as a nutritional supplement to infants and young children (IYC) in less developed areas of China. However, whether 18-month YYB consumption is reasonable needs assessment. This study examined the influence of the duration of YYB consumption on hemoglobin (Hb) levels and anemia prevalence. Data from the Nutrition Improvement Project on Children in Poor Areas of China in 2018-2019 were used. Questionnaires were used to collect information on basic characteristics, dietary status, and YYB consumption. Propensity score matching (PSM) was used to balance confounders. Hb levels and anemia prevalence in IYC with different durations of YYB consumption were compared. After PSM, all covariates were well-balanced, and 1151 pairs of IYC were included in subsequent analyses. During the 1st-9th months of intervention, YYB effectively increased Hb levels and reduced anemia prevalence in the intervention group. During the 10th-18th months of intervention, Hb levels in the control group increased and anemia prevalence decreased, while Hb levels and anemia prevalence fluctuated in the intervention group. In conclusion, YYB was effective in improving nutritional status of infants, but had a limited effect in young children. Nutritional supplements with different quantities or nutrients should be considered for young children.