Prevalence of anemia by causes, and severity in different age groups in India: A Systematic Review and Meta-Analysis

Background: Anemia continues to be a significant public health concern in India, affecting various age groups and carrying substantial economic and health burdens. In India, nutritional anemia, predominantly from iron deficiency, is a significant challenge to public health. Objective: To assess the prevalence of anemia by causes and severity in different age groups among Indians. Methods : We searched different bibliographic databases (such as MEDLINE via PubMed, IMSEAR (WHO Regional Office Library for South-East Asia Region)) and the WHO Micronutrients database. Additionally, we searched the reference lists of the included studies, vital statistics data, government surveillance data and reports, and population censuses and survey data. The search strategy was restricted to studies conducted in India to ensure relevance to the Indian healthcare context, where disease epidemiology, healthcare infrastructure, and treatment protocols differ significantly from global settings. We performed the last search on June 2025. After removing duplicates, we screened all the studies based on titles and abstracts, followed by full-text screening. We extracted the data and analysed it using StataCorp. We used random-effects meta-analysis with 95% confidence intervals. Results: We identified 1648 studies and included 68 studies with 36,18,928 participants. Most studies were conducted on females of reproductive age groups, including pregnant, lactating, adolescents, and adults. The highest prevalence for any type of anemia was reported in children aged 4 to 6 years 93% (95% CI 90 to 95), followed by post-menopausal women 85% (95% CI 80 to 89), adolescents 62% (95% CI 49 to 73), children under-five years 60% (95% CI 45 to 73), and women of reproductive age (WRA) 54% (95% CI 41 to 76). In contrast, infants under-six months had the lowest prevalence 8% (95% CI 5 to 13). Among females, post-menopausal women had the highest prevalence 85% (95% CI 80 to 89), and adolescents had the highest prevalence 39% (95% CI 16 to 68) among males. Conclusion: The highest prevalence of anemia was observed in children between 4 to 6 years of age. Nutritional anemia is the commonest cause of anemia. There is lack of evidence on the prevalence of megaloblastic anemia, hemolytic anemia, anemia due to chronic inflammatory conditions, anemia due to chronic infections, and genetic disorders, necessitating further quality studies. Funding: This work was funded by the Indian Council of Medical Research (ICMR), New Delhi, India under Grant number 5/7/594/1/-RHN Systematic review registration: This review has been registered in PROPSERO (CRD42023459381). https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023459381