Frequently Asked Question
NutritionDo vegans need B12 supplements?
Last reviewed: January 10, 2026
Summary
Yes. B12 is essential and must be supplemented or obtained from fortified foods on a vegan diet. This is not a flaw of veganism—B12 comes from bacteria, and modern food systems remove it from most sources.
Evidence Summary
The clear answer: Yes, vegans need B12 supplementation or reliable fortified foods. Why B12 matters:
- Essential for nerve function and DNA synthesis
- Deficiency causes irreversible neurological damage
- Body stores can mask deficiency for years before symptoms appear Where B12 actually comes from: B12 is produced by bacteria, not by animals or plants. Historically, humans got B12 from:
- Soil bacteria on unwashed produce
- Contaminated water sources
- Fermented foods Modern food