From the Research
Elevated vitamin B12 levels are associated with a higher risk of cancer, and it is essential to investigate potential underlying causes rather than focusing on reducing the B12 level itself. High B12 levels are typically found incidentally during blood tests and often indicate an underlying condition rather than being problematic themselves. Conditions associated with elevated B12 include liver disease, certain blood disorders like myeloproliferative neoplasms and leukemias, kidney disease, and some solid tumors 1. In rare cases, extremely high supplementation might cause acne, rosacea, or skin rashes. Unlike water-soluble vitamins that are easily excreted, B12 is stored in the liver, so excessive supplementation can lead to accumulation.
Some key points to consider:
- Elevated B12 levels may serve as a proxy for poor liver function, and adjusting for liver function can eliminate the association between high B12 levels and mortality 2.
- Vitamin B12 supplementation might decrease serum levels of homocysteine in patients with non-alcoholic fatty liver disease, but further studies are needed to confirm this finding 3.
- B12 levels can be an independent predictor of mortality in patients with acute-on-chronic liver failure, highlighting the importance of monitoring B12 levels in these patients 4.
- A study on children with high vitamin B12 values found that these levels are usually benign, but some patients may develop leukemia later, emphasizing the need for follow-up and investigation of underlying causes 5.
Normal B12 blood levels typically range from 200-900 pg/mL, with levels above this potentially warranting further investigation depending on your clinical situation. If you have unexpectedly high B12 levels, it's crucial to consult with your healthcare provider to investigate potential underlying causes and develop an appropriate management plan.