Vitamin B12 deficiency: epidemiological trends and risk factors
- 1Jamia Hamdard University , ,
- 2Department of Pediatrics, Hamdard Institute of Medical Sciences and Research , ,
Abstract
Vitamin B12 (cobalamin) can only be obtained from animal food sources and is important for several functions, including DNA synthesis, haematopoiesis and myelination. It is one of the most common micronutrient deficiencies worldwide. Accurate estimates of the global burden remain difficult to ascertain because studies differ in the biomarker used (total serum/plasma B12, holotranscobalamin, or methylmalonic acid) and in the diagnostic cut-off applied, and because countrywide, longitudinally comparable data remain limited. This narrative review conducted following a defined literature search and selection strategy described in Section 1.1—synthesizes the current epidemiology of vitamin B12 deficiency, compares India's experience with other nations, and examines how reported prevalence has changed over the past 50 years. Pooled meta-analytic estimates indicate that approximately 50% of the Indian population is affected by vitamin B12 deficiency, among the highest rates reported worldwide. Reported prevalence rises across the life course, from 14% to 17% to 31% to 48% to 62% in pre-schoolers, school-aged children, adolescents, adults and the elderly respectively, with substantial regional heterogeneity within India (Section 2.8). Prevalence among pregnant women has been reported to range from 40% to 70%. The most consistently reported associated factors are dietary pattern (vegetarianism), low socioeconomic status, advancing age and female sex; because the underlying studies are predominantly cross-sectional, these should be read as associations rather than established causal pathways. Reported prevalence has remained high across every assessment period from the 1970s to the present, though this pattern is reconstructed from independent cross-sectional studies rather than a single longitudinal cohort (Section 4). We conclude that improved, harmonized diagnostic criteria, targeted screening, and reconsideration of current food-fortification standards are needed, while noting the implementation and evidentiary challenges that fortification scale-up in India still faces (Section 5).
Related
- Epidemiological trends, projections, and attributable risk factors of esophageal cancer: a comparative study of four Western Pacific countries, 1990–2040
- Prevalence and associated factors of vitamin B12 deficiency among Vietnamese patients with type 2 diabetes receiving metformin therapy: a cross-sectional study
- Vitamin D Deficiency and Associated Factors Among Postpartum Women in Türkiye: A Primary Care Cross-Sectional Study
- Trends in Modifiable Risk Factors Contributing to Ischemic Heart Disease Mortality in Afghanistan: Estimates From the Global Burden of Disease Study 2023 (1999-2023)
- Epidemiological characteristics, risk factors, and prevention and control progress of ischemic heart disease in elderly people in China
BibTeX
@article{toteja2026vitamin,
title = {{Vitamin B12 deficiency: epidemiological trends and risk factors}},
author = {Gurudayal S. Toteja and Nishant Toteja},
journal = {Frontiers in nutrition},
year = {2026},
month = oct,
doi = {10.3389/fnut.2026.1930037},
url = {https://europepmc.org/article/PMC/PMC13719891},
note = {CC BY},
}
RIS
TY - JOUR
TI - Vitamin B12 deficiency: epidemiological trends and risk factors
AU - Gurudayal S. Toteja
AU - Nishant Toteja
PY - 2026
DA - 2026/10/16
JO - Frontiers in nutrition
DO - 10.3389/fnut.2026.1930037
UR - https://europepmc.org/article/PMC/PMC13719891
AB - Vitamin B12 (cobalamin) can only be obtained from animal food sources and is important for several functions, including DNA synthesis, haematopoiesis and myelination. It is one of the most common micronutrient deficiencies worldwide. Accurate estimates of the global burden remain difficult to ascertain because studies differ in the biomarker used (total serum/plasma B12, holotranscobalamin, or methylmalonic acid) and in the diagnostic cut-off applied, and because countrywide, longitudinally comparable data remain limited. This narrative review conducted following a defined literature search and selection strategy described in Section 1.1—synthesizes the current epidemiology of vitamin B12 deficiency, compares India's experience with other nations, and examines how reported prevalence has changed over the past 50 years. Pooled meta-analytic estimates indicate that approximately 50% of the Indian population is affected by vitamin B12 deficiency, among the highest rates reported worldwide. Reported prevalence rises across the life course, from 14% to 17% to 31% to 48% to 62% in pre-schoolers, school-aged children, adolescents, adults and the elderly respectively, with substantial regional heterogeneity within India (Section 2.8). Prevalence among pregnant women has been reported to range from 40% to 70%. The most consistently reported associated factors are dietary pattern (vegetarianism), low socioeconomic status, advancing age and female sex; because the underlying studies are predominantly cross-sectional, these should be read as associations rather than established causal pathways. Reported prevalence has remained high across every assessment period from the 1970s to the present, though this pattern is reconstructed from independent cross-sectional studies rather than a single longitudinal cohort (Section 4). We conclude that improved, harmonized diagnostic criteria, targeted screening, and reconsideration of current food-fortification standards are needed, while noting the implementation and evidentiary challenges that fortification scale-up in India still faces (Section 5).
SN - 2296-861X
ER -