Vitamin B12: Are You Getting It?

by Jack Norris, RD

Summary

1. Vegans Need B12
2. Myths
3. Recommendations
4. Vegan Sources

Deficiency

5. Overt
6. Mild: Elevated Homocysteine
7. Depression

The B12 Molecule

8. Analogues
9. Digestion, Absorption, and Transport
10. Coenzyme Functions

Measuring

11. Blood B12 Levels: Not Reliable
12. Should I Get My B12 Status Tested?

B12 Status

13. Vegans Infants & Toddlers
• Vegan Infants & Toddlers with B12 Deficiency
14. Vegan Children & Teenagers
15. Vegan Adults
16. Elderly Vegetarians
17. Raw Foodist Vegans
18. Macrobiotics
19. Lacto-Ovo Vegetarians
20. Individual Cases of Deficiency
21. Immerman - The Exception

Plant Sources

22. Measuring B12: Why the Confusion?
23. B12 in Tempeh, Seaweeds, Organic Produce, and Other Plant Foods
24. Are Intestinal Bacteria a Reliable Source of B12?
25. B12 and Non-Human Animals

Conclusion

26. Conclusion: Can a Natural Diet Require Supplements?

Appendices

1. How Recommendations were Formulated
2. People Over Age 50
3. People Who Should Not Take the Cyanocobalamin Form of B12
4. Smokers and Cyanocobalamin
5. Non-cyanocobalamin B12 Supplements
6. SAMe
7. Ways to Get B12 Deficiency
8. Elevated Serum B12 and Increased Risk of Disease
9. Conditions That Increase B12 Levels
10. B12-Related Laboratory Values
11. Plant Sources of Folate
12. Figure: Methionine-Homocysteine-Folate-B12 Cycle

Acknowledgements

• Vegan Outreach for supporting this work.
• Tom Billings for research assistance.
• Stephen Strauss for research and sharing correspondence.
• Michael Greger, Lauren Panos, and Stephen Walsh for various contributions.