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Higher mortality risk with high B12 blood levels?

A Dutch study found a significantly higher mortality rate among patients with high plasma levels of vitamin B12 than among those with low plasma vitamin B12 levels. The levels found were mostly within the normal range. The researchers have no explanation for the association they found between the vitamin B12 levels and the elevated mortality rate. One limitation of the study was that it could not provide convincing evidence for a causal relation between the vitamin B12 blood levels and mortality.

  • Although an association has been found, there is no convincing evidence for a causal relation between the higher vitamin B12 blood levels and the increased mortality rate found.
  • The article does not mention people with medically proven vitamin B12 deficiency.
  • Nor does the article say anything about the possible risks of vitamin B12 supplementation.

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  • Leo M.L. Stolk, dr