Childhood Iron Deficiency Research Grew Annually While Persistent Global Gaps Remain

A comprehensive bibliometric evaluation spanning two decades of medical literature reveals that global research on nutritional strategies for childhood iron-deficiency anemia expanded at an annual rate of 3.28 percent from 2006 to 2025, alongside persistent geographic imbalances. Drawing on 1,588 peer-reviewed articles from Web of Science, Scopus, and PubMed, the investigation provides a structural mapping of publication volume, authorship networks, institutional leadership, and clinical trends. Scientific output peaked between 2021 and 2025, driven by expanding international attention toward pediatric micronutrient deficiencies. However, the analysis identifies a pronounced global disparity: scientific output remains heavily concentrated within high-income nations, whereas low- and middle-income regions facing the greatest burden of childhood anemia remain starkly underrepresented as primary producers of academic literature.

Iron deficiency represents the most common childhood nutritional disorder, carrying physiological and cognitive repercussions that extend well beyond hematological deficits. World Health Organization estimates indicate that 40 percent of children aged 6 to 59 months worldwide were affected by all-cause anemia in 2019, with regional figures exceeding 60 percent in parts of Sub-Saharan Africa and South Asia. While iron deficiency is recognized as the leading contributor, childhood anemia remains multifactorial, shaped by other micronutrient deficits, infectious diseases, inflammation, and inherited hemoglobin disorders. In developing children, insufficient iron intake and low bioavailability during early development impair hemoglobin formation and cerebral oxygen delivery, contributing to stunted physical growth, impaired cognitive development, and reduced school performance. Because earlier bibliometric assessments focused predominantly on single databases such as Web of Science, the research team conducted a multi-database analysis across three platforms to map research priorities, trace methodological developments, and evaluate geographic patterns in international collaboration.

To build a comprehensive dataset and minimize indexing biases, the researchers implemented a structured search across Web of Science, Scopus, and PubMed for literature published from 2006 to 2026. The search protocol combined controlled keywords covering pediatric populations, iron deficiency, anemia, and nutritional or dietary interventions. Four independent reviewers applied predefined eligibility criteria using a standardized analytical template. Inclusion was limited to peer-reviewed journal articles evaluating pediatric populations under 18 years of age across medicine, nursing, agriculture, and biological sciences. Publications that were not original articles—including editorials, books, book chapters, and letters—as well as studies focused on pregnant individuals under 18 years were excluded. The initial search retrieved 781 articles from Web of Science, 577 from Scopus, and 230 from PubMed. Data cleaning, keyword standardization, and deduplication were conducted in RStudio and Biblioshiny, producing a final unified collection of 1,588 validated articles for mapping in VOSviewer and RStudio.

Statistical analysis across the completed 2006–2025 period examined 1,582 articles, deliberately excluding six records indexed in January 2026 to prevent partial-year data from distorting annual growth calculations and temporal trajectories. Across this 20-year span, the annual publication growth rate was 3.28 percent, the average article age reached 9.68 years, and documents received an average of 20.19 citations. Output remained steady at a minimum baseline of 59 publications per year during the early study window, before trending progressively upward. Despite minor contractions in 2011 and 2014, publication numbers recovered rapidly in 2015 and culminated in an annual peak in 2025, confirming sustained research attention. Analysis of document typologies indicated that original research articles predominated with 1,137 entries, alongside 272 narrative reviews, 165 clinical studies, comparative studies, and case reports, and 8 systematic reviews. In total, the literature incorporated 5,224 identifier-based Keywords Plus and 3,190 author-provided keywords across 579 publishing journals.

An evaluation of publishing sources demonstrated that scientific dissemination in childhood iron nutrition adheres closely to Bradford’s Law, with research concentrating within a narrow cluster of specialized periodicals. Among the 579 journals identified, Nutrients ranked first with 83 publications, followed by the American Journal of Clinical Nutrition and The Journal of Nutrition. Together, these three publications accounted for 12.5 percent of the total analyzed corpus, illustrating their central role in communicating pediatric nutritional findings. Longitudinal analysis revealed marked differences in journal growth trajectories over time. Traditional periodicals—including The Journal of Nutrition, the American Journal of Clinical Nutrition, Public Health Nutrition, and the Food and Nutrition Bulletin—maintained steady, linear growth between 2006 and 2013, with cumulative outputs stabilizing between 35 and 50 articles. In contrast, Nutrients exhibited an exponential surge starting in 2013, surpassing established journals by approximately 2020 to become the leading dissemination channel for studies on food fortification, micronutrient bioavailability, and intervention efficacy.

Author productivity closely matched the theoretical expectations of Lotka’s Law, which describes the structured distribution of scientific output within a discipline. Out of 7,166 contributing authors, an average of 6.32 co-authors per paper was observed, with 62 authors accounting for 69 single-authored documents. Empirical modeling of author productivity showed a robust fit with Lotka’s model, yielding an estimated exponent beta of 2.56, a constant C of 0.46, and a coefficient of determination of 0.94. Approximately 81.68 percent of authors (5,876 individuals) published only one article, 10.79 percent (776 authors) published two, and merely 0.04 percent (3 authors) reached ten articles. Longitudinal tracking identified Zimmermann M. as the most prolific researcher, maintaining continuous output from 2006 to 2026. The most-cited individual publications globally were authored by Sazawal S. with 756 citations, Baker R. with 726 citations, and Dewey K. with 659 citations, concentrating primarily in high-impact medical journals such as The Lancet and Pediatrics.

Geographic analysis revealed marked international disparity in scientific output, with the United States leading global volume and total citations. American researchers produced 964 publications between 2006 and 2026, amassing 9,413 total citations and averaging 37.8 citations per article. India ranked second in overall volume with 459 publications, displaying rapid acceleration since 2019, but recorded a lower average of 16.7 citations across 2,102 total citations. Canada placed third with 294 publications (1,766 citations; 33.3 average), followed by China with 271 publications (938 citations; 13.6 average), Brazil with 255 publications (906 citations; 12.6 average), and Australia with 195 publications (1,354 citations; 38.7 average). Despite lower publication counts, Switzerland and France recorded the highest average citations per article at 51.1 (2,504 citations) and 50.3 (855 citations), respectively. Institutional output was led by the University of Toronto, followed by the University of California, Davis, and the University of Otago, reflecting a heavy concentration of pediatric nutrition research within well-resourced biomedical centers in high-income countries.

Collaboration network mapping highlighted structural hierarchies and uneven international partnerships across scientific jurisdictions. Overall, 22.76 percent of the analyzed papers involved international co-authorship. The United States operated as the central structural node connecting networks across Europe, Asia, and Oceania, though domestic research accounted for the predominant share of output in the United States, India, Brazil, China, and Canada. In contrast, countries such as Switzerland, Turkey, Iran, Australia, and the United Kingdom exhibited higher proportions of multi-country collaborative research. Notably, academic institutions across Sub-Saharan Africa, Latin America, and parts of Asia were underrepresented in the scientific literature, despite these regions experiencing the highest global prevalence of childhood anemia. The authors emphasized that this institutional imbalance creates challenges regarding research autonomy and local capacity, pointing to the need for equitable collaboration models that ensure interventions are contextualized to regional diets, public health infrastructure, and socioeconomic conditions.

Multivariate correspondence analysis (MCA) and keyword co-occurrence mapping clarified the thematic organization of the analyzed literature. The two-dimensional MCA model explained 96.32 percent of total inertia, with Dimension 1 capturing 92.16 percent and Dimension 2 accounting for 4.16 percent, confirming that the dimensional projection effectively represented term variance. The thematic landscape separated into two primary clusters: a clinical and interventional group centered on terms such as iron supplementation, ferrous sulfate, and blood ferritin levels, and an epidemiological group organized around population descriptors including infant, child, and nutritional assessment. Cross-cutting connections between these domains illustrated the ongoing translation of clinical diagnostic markers into population-level public health programs.

Thematic evolution across the 20-year span revealed three overlapping developmental phases, reflecting broadening scientific inquiry from mass public health interventions toward biological mechanisms and personalized nutrition. Phase 1 (2006–2012) focused on community dietary assessment, day-care settings, conventional iron fortification, and supplementation. Phase 2 (2013–2018) emphasized epidemiological characterization, clinical trial evaluation, and hematological monitoring using hemoglobin and ferritin. Phase 3 (2019–2026) broadened into regulatory biomarkers such as hepcidin, zinc protoporphyrin, vitamin D interactions, and gut microbiota dysbiosis resulting from unabsorbed iron, alongside clinical evaluation of ferric carboxymaltose for oral intolerance. Crucially, the authors noted several study limitations, including the restriction to English-language publications indexed in selected databases and challenges in standardizing citation and author metadata. The researchers cautioned that bibliometric trends reflect scientific publication activity and thematic interest rather than verified clinical efficacy or safety, underscoring that emerging individualized strategies must complement rather than replace proven universal food fortification and iron supplementation programs.

Subject of Research: Bibliometric analysis of global research trends in nutritional strategies for childhood iron-deficiency anemia

Article Title: Global research landscape and emerging trends in nutritional strategies for childhood iron-deficiency anemia: a bibliometric analysis (2006–2026)

Article References: Jamanca-Gonzales, N. C., Cruz-Sánchez, T. H., Chambergo-Valverde, H. C., Jauregui-Sueldo, C. J., Muñoz-de-la-Torre, R. J., Reginaldo-Huamani, R., Román-Paredes, N. O., Romero-Acevedo, J. H., & Toral-Santillan, E. J. (2026). Global research landscape and emerging trends in nutritional strategies for childhood iron-deficiency anemia: a bibliometric analysis (2006–2026). Frontiers in Nutrition, 13, 1962443. https://doi.org/10.3389/fnut.2026.1962443

Image Credits: AI Generated

DOI: 10.3389/fnut.2026.1962443

Keywords: iron-deficiency anemia, pediatric nutrition, bibliometric analysis, food fortification, iron supplementation, ferritin, hepcidin, micronutrient powders, gut microbiota, ferrous sulfate, ferric carboxymaltose, hemoglobin, Lotka's Law, Bradford's Law, public health policy, zinc protoporphyrin, nutritional epidemiology, global health disparities