Although globally the numbers of children diagnosed with failure to thrive (FTT) have decreased, FTT is still a serious pediatric problem. We aimed to investigate the effects of zinc supplementation for 6 months on growth parameters of infants and children with FTT.

In this retrospective study, of the 114 participants aged between 4 months and 6 years, 89 were included in the zinc supplementation group and were provided with nutrition counseling plus an oral zinc supplement for 6 months. The caregivers of the 25 participants in the control group received nutrition counseling alone. Medical data of these children, including sex, age, height, weight, serum zinc level, and serum insulin-like growth factor 1 (IGF1) level were analyzed.

Zinc supplementation for 6 months increased weight-for-age Z-score and serum zinc levels (5.5%) in the zinc supplementation group of underweight category children. As for stunting category, height-for-age Z-score of the participants in the zinc supplementation group increased when compared with the baseline, and serum zinc levels increased in the normal or mild stunting group. Serum IGF1 levels did not change significantly in any group. Thus, zinc supplementation was more effective in children in the underweight category than those in the stunted category; this effect differed according to the degree of the FTT.

These findings suggest that zinc supplementation may have beneficial effects for growth of infants and children with FTT, and zinc supplementation would be required according to degree of FTT.