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Lifestyle
- Regular medical check-ups
- Monitoring for gastrointestinal health
- Avoiding excessive alcohol consumption
Blutwerte · Marker
Vitamin B12
Cobalamin · Cyanocobalamin · Methylcobalamin · B12
Vitamine & Nährstoffe
- Einheit:
- pmol/L
- Abbreviation
- B12
Vitamin B12 test quantifies the level of cobalamin in the blood, reflecting its availability for cellular processes.
Reference Ranges
Reference
148–740pmol/L
148
300
600
740
LowNormalHigh
Reference
Optimal
Unit · pmol/LRanges may vary slightly based on age and laboratory standards.
Overview
Übersicht
Vitamin B12, also known as cobalamin, is a water-soluble vitamin essential for various biological processes, including DNA synthesis, red blood cell formation, and neurological function. It acts as a cofactor in the cytosolic methionine synthase reaction and the mitochondrial methylmalonyl CoA mutase reaction, both crucial for cellular metabolism. Researchers found that B12 deficiency can lead to megaloblastic anemia, characterized by ineffective red blood cell production, and neurological impairments due to defective myelin synthesis. Clinically, B12 levels are important in diagnosing and managing conditions such as anemia, cognitive impairments, and potentially autism spectrum disorders. In athletic performance and biohacking, B12 is valued for its role in energy metabolism and nervous system health, potentially influencing endurance and cognitive function. However, researchers observed that B12 levels can be affected by factors such as dietary intake, malabsorption, and genetic predispositions. Testing should consider these variables, and fasting is not typically required. Time of day and recent dietary intake can influence results, so consistency in testing conditions is advised.
Klinische Bedeutung
Reduced B12 levels indicate potential deficiencies leading to megaloblastic anemia and neurological issues. Elevated levels are less common and may suggest supplementation or liver disease.
Dynamics
Trend Interpretation
Rising Values
Progressively rising B12 levels may indicate excessive supplementation or liver dysfunction. Re-test in 3 months if levels are unexpectedly high.
Falling Values
Falling B12 levels suggest worsening absorption or dietary intake, warranting further investigation.
Re-test Interval
4 weeks if outside optimal range
Etiology
Causes — High & Low
Cause
Elevated Levels
- Excessive supplementation
- Liver disease
- Leukemia
- Renal failure
- Polycythemia vera
Cause
Low Levels
- Dietary deficiency
- Malabsorption syndromes
- Pernicious anemia
- Gastrointestinal surgery
- Increased requirement during pregnancy
Protocol
How to Optimize
Lever
Nutrition
- Increased intake of animal products
- Fortified cereals
- Nutritional yeast
Lever
Supplementation
- Cyanocobalamin
- Methylcobalamin
- Hydroxocobalamin
Note:
Consult a healthcare provider before starting supplementation, especially if you have underlying health conditions.
Testing Guidelines
✓Fasting Not Required
✓Not Time-Sensitive
Testing Frequency
Annually for adults at risk of deficiency, more frequently if symptomatic or during pregnancy.
Interfering Factors
- Recent B12 injections
- Certain medications
- Pregnancy
Related Peptides & Hormones
Folate
hormone or peptideCorrelated with
Open Research Questions
Current research suggests that the relationship between vitamin B12 levels and conditions such as autism spectrum disorder remains inconclusive, with inconsistent findings across studies and a lack of longitudinal data to account for individual variability. Researchers have not yet established optimal reference ranges or targets for B12 levels in various populations, particularly in pregnant women and children. Additionally, clinical questions remain unanswered regarding the precise mechanisms linking B12 deficiency to neurodevelopmental outcomes and the impact of dietary intake on B12 status.
21 Research Publications
716
Total Citations
2
Human/RCT
2.9
Avg. Influence
2025
Latest
Sort
Filter
01Top
#01
How I treat anemia in pregnancy: iron, cobalamin, and folate.
ReviewInfluence7.0
177
This study discussed the prevalence of anemia in pregnancy, focusing on the roles of iron, vitamin B12, and folate deficiencies. Researchers highlighted the rising prevalence of cobalamin deficiency in pregnant women and its potential impact on fetal health.
02Top
#02
Vitamin B12 status in health and disease: a critical review. Diagnosis of deficiency and insufficiency - clinical and laboratory pitfalls.
ReviewInfluence5.0
153
This review focused on the complexities of diagnosing vitamin B12 deficiency, noting that it can present as various illnesses. Researchers found that current diagnostic tests have limitations, which can lead to misdiagnosis and inappropriate treatment.
03Top
#03
Severe megaloblastic anemia: Vitamin deficiency and other causes.
ReviewInfluence6.0
101
This study examined the causes of megaloblastic anemia, highlighting vitamin B12 deficiency as a common factor. Researchers found that diagnosis relies on specific laboratory findings and that treatment involves addressing the underlying cause, such as vitamin supplementation.
04
#04
Laboratory testing for cobalamin deficiency in megaloblastic anemia.
ReviewInfluence2.0
71
This study focused on laboratory testing for cobalamin deficiency in megaloblastic anemia. Researchers found that traditional serum cobalamin tests may not accurately reflect vitamin B12 status, suggesting the need for alternative biomarkers to improve diagnostic accuracy.
05
#05
Omeprazole and vitamin B12 deficiency.
ReviewInfluence1.0
45
This study examined the impact of omeprazole on vitamin B12 absorption, finding that it may hinder the release of B12 from dietary proteins. Researchers noted that while there is a concern about potential deficiency, the clinical significance remains unclear, warranting further research into dietary factors that may enhance absorption.
06
#06
Vitamin B12 deficiency.
ReviewInfluence1.0
39
Researchers explored the complexities of vitamin B12 deficiency, noting its various causes including malabsorption and dietary limitations. They found that B12 deficiency can lead to significant health issues affecting the blood and nervous system, with diagnosis relying on clinical suspicion and laboratory tests.
07
#07
Vitamin B12 deficiency and metabolism-mediated thrombotic microangiopathy (MM-TMA).
ReviewInfluence2.0
38
Researchers examined the relationship between vitamin B12 deficiency and thrombotic microangiopathy (TMA). They found that severe B12 deficiency can mimic TMA symptoms, highlighting the importance of prompt identification and treatment of B12 deficiency.
08
#08
[Vitamin B12 (cobalamin)].
ReviewInfluence2.0
29
This study reviewed the clinical significance of vitamin B12 deficiency, highlighting its association with megaloblastic anemia and neurological disorders. Researchers discussed the biochemical parameters used to diagnose both clinical and subclinical deficiency.
09
#09
The application and interpretation of laboratory biomarkers for the evaluation of vitamin B12 status.
Harrington Dominic J, et al. · Annals of clinical biochemistry · 2025
ReviewInfluence2.0
23
Researchers examined the biomarkers for assessing vitamin B12 status, noting the common use of serum B12 tests. They found that no single test is definitive for deficiency, and a combination of biomarkers may provide a more accurate assessment.
Key findings
- 01Researchers observed that different biomarkers can indicate vitamin B12 deficiency or sufficiency.
- 02The review identified the significance of accurate interpretation of test results for proper health assessments.
- 03Researchers noted that understanding these biomarkers is crucial for preventing potential health issues related to vitamin B12 status.
10
#10
Diagnostic difficulties in pernicious anemia.
ReviewInfluence1.0
15
This study discussed the diagnostic challenges of pernicious anemia, the leading cause of vitamin B12 deficiency. Researchers found that diverse clinical presentations and limitations of diagnostic tests complicate the identification of this condition.
Clinical Trials (8)
8
Total Trials
666
Total Enrolled
Effects of Vitamin B12 and Natural Orange Extract, and Their Combination on Physical and Mental Performance
NCT07341789ENROLLING_BY_INVITATION
Sponsor
Francisco Javier Martínez Noguera
Enrollment
20
Started
2025
Primary outcome
Wingate test
Vitamin b12Supplementation During Endurance PerformanceFlavonoidsMental FatigueBiomarker Feedback
Vitamin B12 Dose Escalation Trial in Pregnancy
Sponsor
George Washington University
Enrollment
50
Started
2023
Primary outcome
Assessing the steady state pharmacokinetics of B12 upon oral administration in pregnant women.
Vitamin B 12 Deficiency
Effect of Daily Consumption of Vitamin B12 Fortified Yoghurt on Vitamin B12 Status in Older Adults
NCT05993962COMPLETED
Sponsor
University of British Columbia
Enrollment
80
Started
2019
Primary outcome
Serum total B12 concentration
Vitamin B 12 Deficiency
Vitamin B12 Supplementation to Improve B12 Status and Child Development
NCT03258385COMPLETED
Sponsor
International Centre for Diarrhoeal Disease Research, Bangladesh
Enrollment
155
Started
2017
Primary outcome
Change in concentrations of biomarkers of vitamin B12 in mother-child pairs
Early Pregnancy
Parental One-carbon Folate and Choline Nutrition Modulates Risk of Off-spring Cancer Development: Human Cohort Study
NCT02266641COMPLETED
Sponsor
National Taiwan University Hospital
Enrollment
118
Started
2014
Primary outcome
Assessment of maternal one-carbon nutrient (folate, choline, betaine, Vitamine B12) intake at the first trimester visit of pregnancy
Off-spring Cancer Risk
Vitamin B12 Status and Response to Vitamin B12 Supplementation in Patients With Parkinson's Disease
Sponsor
Emory University
Enrollment
57
Started
2006
Primary outcome
Vitamin B12 concentration
Parkinson's Disease
Effect of Homocysteine-lowering Therapy With Folic Acid, Vitamin B12, and Vitamin B6 on Endothelium-dependent Vasodilatation of Forearm Resistance Vessels in Patients With Coronary Heart Disease
Sponsor
Insel Gruppe AG, University Hospital Bern
Enrollment
36
Started
2005
Primary outcome
Flow mediated dilatation (FMD)
Cardiovascular DiseaseEndothelial Dysfunction
Holotranscobalamin Remains Unchanged During Pregnancy
NCT00467623COMPLETED
Sponsor
University of Aarhus
Enrollment
150
Started
1995
Vitamin B12 Deficiency
Publication Trend
Research publications about Vitamin B12 over time
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