Global Prevalence of Adolescent Use of Nonprescription Weight-Loss Products: A Systematic Review and Meta-Analysis.

Importance: Use of nonprescribed weight-loss products in adolescents is a public health concern that is associated with negative physical and psychological consequences. However, the prevalence of nonprescribed weight-loss product use in adolescents is unknown. Objective: To determine the global prevalence of nonprescription weight-loss product use in children and adolescents. Data Sources: Four databases, including MEDLINE, PsycINFO, CINAHL (Cumulative Index of Nursing and Allied Health), and EMBASE, were searched for quantitative studies that reported prevalence data on use of nonprescription weight-loss products with no restrictions on publication date. The search was performed December 1, 2020, and updated March 6, 2023. Study Selection: Studies were included in the meta-analysis if they reported the prevalence of weight-loss product use, were published in English, and included individuals 18 years or younger. Data Extraction and Synthesis: Data extraction was completed by 2 independent reviewers. Data analysis determined the overall pooled proportion of weight-loss product use in total and during the past week, past 30 days, past year, or lifetime. Inverse variance heterogeneity effect models were used. Main Outcomes and Measures: The main outcome measure was the prevalence of nonprescription weight-loss product use in adolescents for all included studies and over the past week, past month, past year, or lifetime. Subgroup analysis included separation of groups by sex, specific weight-loss product types, geographical location, and study publication time. Results: A total of 90 articles (604 552 unique participants) were included in the meta-analysis. Of these, 50 studies (56%) were from North America. The reported prevalence of weight-loss product use in adolescents was 5.5% (96% CI, 5.5%-5.6%) overall. When identifying use of weight-loss products in the general population, prevalence was 2.0% (95% CI, 1.9%-2.1%) in the past week, 4.4% (95% CI, 4.3%-4.5%) in the past month, 6.2% (95% CI, 6.1%-6.3%) in the past year, and 8.9% (95% CI, 8.6%-9.2%) in their lifetime. Use of weight-loss products was higher among girls than boys. Conclusions and Relevance: This meta-analysis found that use of weight-loss products occurs at high levels in adolescents, especially girls. These findings suggest that, given the ineffectiveness of these products for weight loss coupled with their harmful long-term health consequences, interventions are required to reduce use of weight-loss products in this group.