vitamin B12

Vitamin B12 is made by neither animals nor plants, but actually is made by microbes. Thankfully, in our sanitized world there are safe, cheap, convenient sources. Vitamin B12 deficiency is common in vegans who don’t eat B12 fortified foods or take B12 supplements and can result in paralysis, myelopathy, or psychosis. It is imperative that those eating plant-based diets include B12-fortified foods in their diet or take B12 supplements, especially pregnant or nursing women (see here and here). Testing is not necessary, but supplementing is—it may even increase one’s lifespan. The recommended intake is 4-7 micrograms a day (but to get that much in daily or weekly supplements you have to take much more). Raw food diets are no exception to this rule. Omnivores under age 50 are rarely deficient in vitamin B12 (though may be deficient in other nutrients).

See also the related blog posts: Vitamin B12: how much, how often?, Putting Vitamin B12 Into Perspective, Vegan B12 deficiency: putting it into perspective

Topic summary contributed by Michelle Baer.
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Watch videos about vitamin B12

  • Safest Source of B12
    Safest Source of B12
    Since foods are effectively a package deal, what is the best way to get vitamin B12 (cobalamin)?
  • Vitamin B12 Recommendation Change
    Vitamin B12 Recommendation Change
    Based on two biomarkers of functional vitamin B12 (cobalamin) status, B12 recommendations formulated more than a half century ago may need to be updated.
  • Vegan Epidemic
    Vegan Epidemic
    Vitamin B12 deficiency is common among those eating vegetarian and particularly vegan diets because of failure to take B12 supplements or eat B12-fortifed foods.
  • American Vegans Placing Babies At Risk
    American Vegans Placing Babies At Risk
    Vitamin B12 is an imperative for those eating vegetarian and vegan diets, especially during pregnancy and infancy.
  • Did a Vegan Diet Kill This Baby?
    Did a Vegan Diet Kill This Baby?
    Vitamin B12 deficiency can be life-threatening.
  • Inverted Rabbit Sign
    Inverted Rabbit Sign
    The very real and potentially disastrous effects of vitamin B12 deficiency.
  • Vegetarian’s Myelopathy
    Vegetarian’s Myelopathy
    Vegetarians got a disease named after them.
  • Low Meat or No Meat?
    Low Meat or No Meat?
    Flexitarians versus vegetarians: who lives longer?
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