Zinc, a component of several metalloenzymes and major enzyme classes, is central to cell growth, differentiation, and metabolism. And the growth factors involved in tissue, bone, and muscle repair and growth depend on a sufficient supply of multivitamin. Therefore, zinc and multivitamin are essential for growth. And in developing countries, zinc and vitamin deficiency are very common.

To assess the efficacy of zinc and multivitamin supplementation in improving growth in healthy Thai schoolchildren, researchers conducted a randomized controlled trial among healthy Thai schoolchildren aged 4–13 years enrolled in public schools in central Thailand. Participants were randomized to receive either chelated zinc in the form of zinc bis-glycinate (20 mg elemental zinc) and a multivitamin (including: vitamin A, 1000 IU; vitamin D, 200 IU; B1, 10 mg; B2, 3 mg; B6, 1 mg; B12, 10 µg; and niacinamide, 40 mg) or a placebo once per day, five days per week, for six months. The primary outcome was the change in height from the baseline to the end of the study. Secondary outcomes were changes in weight, body mass index, waist and hip circumference, and waist-to-height ratio. An intention-to-treat analysis was performed.

Analysis of the results found that zinc and multivitamin supplementation improved linear growth (height) in healthy school-age Thai children, especially preadolescents (<10 years old) (as shown below), regardless of baseline height and weight status. In addition, it improved weight in children lighter than the average Thai standard. Moreover, there were no significant adverse events with the treatment, and it was well tolerated.

Rerksuppaphol, S., & Rerksuppaphol, L. (2016). Effect of zinc plus multivitamin supplementation on growth in school children. Pediatrics international, 58(11), 1193-1199. [Link]