Vitamin b12 normal range
Pro Research Analysisby 
Searched over 200M research papers
Understanding the Normal Range of Vitamin B12 Levels
Introduction to Vitamin B12
Vitamin B12, also known as cobalamin, is essential for cellular metabolism, DNA synthesis, and neurological function. Deficiency in this vitamin can lead to significant health issues, including anemia and neurological disorders.
Normal Range of Vitamin B12 Levels
General Population
The normal range of vitamin B12 levels can vary significantly depending on the population and the methods used for measurement. In a study conducted in Konya, Turkey, the normal reference levels for vitamin B12 were found to be 127-606 pg/mL for girls, 127-576 pg/mL for boys, and 127-590 pg/mL for the entire study group. Another study in southwestern Colombia defined normal vitamin B12 levels as above 300 pg/mL, with levels between 200-299 pg/mL considered borderline and levels below 200 pg/mL indicating deficiency.
Methodological Variations
Different methods for measuring vitamin B12 can yield varying results. For instance, a study comparing three methods—radioisotopic, Euglena gracilis, and Lactobacillus leichmannii—found that the normal range varied from 155 to 1470 pg/mL depending on the method used. This highlights the importance of considering the measurement technique when interpreting vitamin B12 levels.
Age and Population-Specific Ranges
Vitamin B12 levels can also vary with age and specific populations. For example, in elderly individuals from urban low-income households, normal serum vitamin B12 levels ranged from 226 to 1200 pg/mL. Another study noted that subnormal levels were more common in individuals aged 70 years and older.
Factors Influencing Vitamin B12 Levels
Medications and Health Conditions
Certain medications, such as metformin used for type 2 diabetes, can significantly affect vitamin B12 levels. The prevalence of vitamin B12 deficiency was notably higher in individuals with type 2 diabetes, especially those on high doses of metformin. Additionally, conditions like pernicious anemia can lead to significantly lower vitamin B12 levels.
Dietary Intake and Absorption
Dietary habits and absorption issues also play a crucial role in determining vitamin B12 levels. Populations with restricted intake of animal-derived foods, such as vegetarians, are at higher risk of deficiency. Malabsorption issues can further exacerbate this risk, leading to both clinical and subclinical deficiencies.
Conclusion
The normal range of vitamin B12 levels varies widely depending on the population, age, and measurement methods. While general ranges can be established, it is crucial to consider individual factors such as diet, medication use, and specific health conditions when interpreting these levels. Establishing population-specific reference ranges and considering methodological differences are essential for accurate diagnosis and management of vitamin B12 deficiency.
Sources and full results
Most relevant research papers on this topic