The effect of zinc supplementation on serum concentration of lipid profile among children and adolescents: A systematic review on randomized controlled trials

Background: New evidence suggests that zinc supplementation may significantly influence serum lipid profile levels and vascular health in children and adolescents. Therefore, this systematic review aims to investigate and summarize published data regarding the effects of zinc supplementation on lipid profiles in children and adolescents. Methods: A systematic search was conducted across multiple databases, including the Cochrane Library, ClinicalTrials.gov, ISI Web of Science, Scopus, and PubMed, up to May 2025. Search terms related to zinc, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglycerides (TG), children, adolescents, and clinical trials were identified using both Medical Subject Headings (MeSH) and non-MeSH terms. The search strategy employed asterisks, parentheses, quotation marks, and Boolean operators (AND/OR) to optimize retrieval of relevant studies. Results: A total of five studies were included in this systematic review. Serum TG, LDL-C, and HDL-C levels were assessed in four studies, and TC levels in five studies. TC decreased in one study. TG and LDL-C levels showed significant reductions compared with placebo in two studies. A significant increase in HDL-C levels was observed in one study. Conclusion: Zinc supplementation may be effective in improving lipid profiles among children and adolescents. However, further well-designed randomized clinical trials involving children and adolescents with varying health conditions, larger sample sizes, different zinc dosages, and longer follow-up periods are strongly recommended to confirm the effectiveness of zinc supplementation in this population.