Association of Dietary Diversity and Odds of Anemia in Children and Adolescents: A Systematic Review and Meta-Analysis of Observational Studies Publisher



Li H¹ ; Moosavian SP² ; Ghanbari N³ ; Mirlohi SH⁴ ; Rahimlou M⁵
Source: BMC Nutrition Published:2025

Abstract

Background: Anemia, characterized by a deficiency in red blood cells or hemoglobin, remains a significant public health concern worldwide, particularly among children and adolescents. Inadequate dietary intake, including micronutrient deficiencies, has been associated with anemia. Dietary diversity, characterized by the consumption of a variety of food groups, may contribute to adequate iron intake and a reduced likelihood of anemia. This systematic review and meta-analysis examined the association between dietary diversity and odds of anemia among children and adolescents. Methods: A comprehensive search of electronic databases (PubMed, Web of Science, Scopus) was conducted for observational studies (cross-sectional or case–control) published before April 2024 that assessed the association between dietary diversity and anemia among children and adolescents. The odds of Bias in Non-Randomized Studies of Exposures (ROBINS-E) tool was used to assess the quality of included studies, ensuring a standardized and rigorous evaluation process. Subgroup analyses explored potential variations in this association based on age group, geographic location, and type of anemia. Results: Nineteen studies (18 cross-sectional and 1 case–control) examined the association between dietary diversity and anemia in children under 5 years old. Pooled analysis revealed a significant association between lower dietary diversity and higher odds of anemia among children aged 0 to 5 years (OR = 1.96; 95% CI: 1.57, 2.45; I2 = 83.6%, τ2 = 0.38 P < 0.001). Ten studies examined the relationship in children and adolescents aged 6–18 years, showing a similar pattern (OR = 1.73; 95% CI: 1.27, 2.36; I2 = 87%, τ2 = 0.44; P < 0.001). Subgroup analyses suggested that the association varied across specific geographic regions. Conclusions: This meta-analysis indicates a significant association between lower dietary diversity and higher odds of anemia in children and adolescents. These findings underscore the importance of dietary diversity as a potential factor related to anemia prevalence. Future research should focus on standardizing dietary diversity assessment methods and incorporating detailed dietary quality measurements. © The Author(s) 2025.