Large-scale review highlights impact of vitamin B12 deficiency on healthcare systems

Global vitamin B12 deficiency is an increasing concern, according to a recently published review that examined its impact on healthcare systems.¹ The study, “Vitamin B12 deficiency and its impact on healthcare: a population-level analysis and call for action,” was published in Frontiers in Nutrition in January 2026, and its aim was to examine the patterns of B12 deficiency on hospitalizations and diseases. It highlighted Brazil as a region for deeper investigation due to various challenges facing the population, including food insecurity and socioeconomic disparities.

Vitamin B12 must be obtained through supplements or food, the study noted, because it cannot be synthesized in the human body. The water-soluble vitamin supports red blood cell production, nerve function, synthesize DNA, and other significant functions, the study explains. Deficiencies can result in the disruption of these functions, and chronic deficiency can result in reduced bone density, mental health conditions and mood disorders, and gastrointestinal diseases.

Study design

The researchers analyzed administrative datasets, which included results from 84 million tests measuring vitamin B12 levels from public and private healthcare systems in Brazil between 2016 and 2023. Unlike other studies, the population was not limited to a subgroup or local setting. The measurements had 99% completeness in age and gender data.

Trends in hospitalizations over time were measured using the Mann-Kendall test. Hospitalizations analyzed included those related to cardiovascular, hematological, neurological, psychological, and gastrointestinal diseases. The researchers noted that they did not suggest a direct connection between test results and hospitalization, but that there was a correlation between deficiencies and hospital admissions for these diseases, in large populations levels.

The associations between vitamin B12 deficiency and other causes of hospitalization were evaluated using the Pearson correlation test.

Study results

The number of measurements over the test period increased twelvefold, from 2 million to 25 million. Out of the total measurements, 35 million were from public health institutions and 47.8 million were from private.

• Over the study period, hospitalizations connected with deficiencies in vitamin B12 and associated diseases increased by 32%
• Vitamin B12 testing was requested more often in private than public healthcare systems
• Female patients underwent testing 2.3 more times than male patients and also demonstrated abnormal results four times more often

Regional differences in the number of measurements highlighted the differences in access to healthcare, demand for diagnostics, and reliance on private healthcare in the country.

“This population-based study highlights a progressive increase in vitamin B12 deficiency-related hospitalizations, suggesting a previously underrecognized public health burden,” the researchers concluded. “Additionally, these findings underscore the correlation between vitamin B12 deficiency, other B vitamin deficiencies, and relevant clinical diseases.”

Some of the implications from the study results include incorportating vitamin B12 screenings for at-risk populations and the potential benefit of national supplementation and fortification programs.

Impact on healthcare systems

The results pointed to the importance of early detection, routine screening, and strategies to reduce impact on healthcare systems, the researchers noted. Recognizing the impacts of vitamin B12 deficiency also has clinical and economic implications, specifically by reducing hospitalizations and supporting at-risk groups. “These findings are intended to inform prevention strategies and strengthen national health policies aimed at early detection and management of vitamin B12 deficiency,” they explain.

Both biological and environmental factors were identified as factors in vitamin B12 status, highlighting the need for targeted nutritional and dietary supplemental interventions.

Reference

1. de Carvalho, LP.; Akamine, N.; Di Pietro, MS.; França, CN.; Oliveira, R.; Lopes, RD. Vitamin B₁₂ deficiency and its impact on healthcare: a population-level analysis and call for action. Front. Nutr. 2026. 12:1701661. DOI: 10.3389/fnut.2025.1701661