Vitamin B12 Sources and Bioavailability

  title={Vitamin B12 Sources and Bioavailability},
  author={Fumio Watanabe},
  journal={Experimental Biology and Medicine},
  pages={1266 - 1274}
  • F. Watanabe
  • Published 1 November 2007
  • Biology, Medicine
  • Experimental Biology and Medicine
The usual dietary sources of vitamin B12 are animal foods, meat, milk, egg, fish, and shellfish. As the intrinsic factor-mediated intestinal absorption system is estimated to be saturated at about 1.5–2.0 μg per meal under physiologic conditions, vitamin B12 bioavailability significantly decreases with increasing intake of vitamin B12 per meal. The bioavailability of vitamin B12 in healthy humans from fish meat, sheep meat, and chicken meat averaged 42%, 56%–89%, and 61%–66%, respectively… 

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