From the Research
Hypervitaminosis B12, or elevated vitamin B12 levels, typically does not cause specific symptoms on its own, but rather, symptoms are related to the underlying condition causing the elevation. The symptoms that may occur are often nonspecific and can include fatigue, headaches, dizziness, anxiety, and gastrointestinal issues like nausea or diarrhea, as noted in various studies 1, 2, 3, 4, 5. In rare cases, very high B12 levels might cause skin manifestations like acne or rosacea, as reported in a case study 4.
Common Underlying Causes
Some common underlying causes of elevated vitamin B12 levels include:
- Liver disease
- Certain blood disorders like myeloproliferative neoplasms
- Kidney disease
- Some cancers, as suggested by a systematic review 5 and a cohort study 3
Importance of Medical Evaluation
It's crucial to understand that high B12 levels are usually a marker of disease rather than a disease itself, so treatment focuses on addressing the underlying condition rather than lowering B12 directly. If you have unexplained elevated B12 levels, medical evaluation is necessary to determine the cause, as it could indicate a serious underlying health issue requiring specific treatment. This is because elevated B12 levels have been associated with a higher risk of cancer and potentially other health issues, as indicated by recent research 3, 5.
Clinical Presentation
Unlike B12 deficiency, which has well-defined symptoms, hypercobalaminemia's clinical presentation is more variable and indirect. The evidence suggests an association between elevated B12 and a higher risk of cancer, with risk ratios ranging from 1.88 to 5.9, as summarized in a systematic review 5. Therefore, it is essential to approach elevated vitamin B12 levels with caution and thoroughly investigate the underlying cause to ensure appropriate management and prevention of potential complications.