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  1. Health and Nutrition News

  2. Feb 11, 2020

Vitamin B12: You Need a Little, But Getting Too Much Could Be Dangerous

High blood levels of vitamin B12 are associated with increased mortality risk, according to a study published in JAMA Network Open. In a study population of more than 5,000 participants, those with the highest plasma B12 levels were found to have a higher mortality rate, compared to those with the lowest plasma B12 levels. While the underlying mechanism behind the associated risk remains unclear, the authors note a potential link between excessive B12 levels and kidney disease and liver damage.


Flores-Guerrero JL, Minovic I, Groothof D, et al. Association of plasma concentration of vitamin B12 with all-cause mortality in the general population in the Netherlands. JAMA Netw Open. 2020;3:e1919274-e1919287.

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