Vitamin B-12

Where do vegetarians and vegans get their B12?

Vitamin B12 is the only nutrient that vegetarians and vegans can’t receive without supplements or fortified foods. But it is definitely possible to reach your B12 requirements on a plant-based diet.

This article contains answers to frequently asked Vitamin B12 questions and practical suggestions for meeting your B12 needs, all backed up with quotes from registered dietitians. All information in quotes is from articles written by registered dietitian Jack Norris here and here, the American Dietetic Association’s position paper on vegetarian diets, and an article by registered dietitian Reed Mangels.

1. How much B12 do I need?

If you are under age thirteen, but over nine, you need 1.8 micrograms of Vitamin B12 per day.

If you are over age thirteen, you need about 2.4 micrograms of Vitamin B12 per day.

To reach this requirement, see questions four and five. When choosing a supplement or fortified food, choose one that provides the daily Vitamin B12 requirements.

2. Is it possible to get enough B12 on a plant-based diet?

Yes, you can receive enough B12 on a vegetarian or vegan diet, as you can receive enough of every nutrient on a plant-based diet. According to the American Dietetic Association, “a [total] vegetarian diet can meet current recommendations for all of these nutrients [protein, n-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B-12]”

3. Are animals a better source of B12 than plants?

This is a trick question. Vitamin B12 does not come from plants or animals. Registered Dietitian Reed Mangels states that “neither plants nor animals make vitamin B12. Bacteria are responsible for producing vitamin B12.” According to registered dietitian Jack Norris, “vitamin B12, whether in supplements, fortified foods, or animal products, comes from micro-organisms.”

These microorganisms are in both plants and animals. They are found mostly in animals, and not in any significant amount in plants. Therefore, animals are a better source of these bacteria than plants. However, these bacteria make up B12 supplements, and these supplements are just as good a source a source of B12 as animals are.

4. How can I get enough B12?

According to registered dietitian Jack Norris, “to get the full benefit of a vegan diet, vegans should do one of the following:

  1. Eat fortified foods two or three times a day to get at least three micrograms of B12 a day or
  2. Take one B12 supplement daily providing at least 10 micrograms or
  3. Take a weekly B12 supplement providing at least 2000 micrograms.”

5. What are some high B12 foods?

No plant food source is nutritious enough. You should always take a supplement or eat fortified foods. Nori, spirulina, sea vegetables, miso, nutritional yeast and tempeh contain some B12. According to registered dietitian Reed Mangels, “these products, however, are not reliable sources of the vitamin.” The American Dietetic Association’s Position Paper states that “[n]o unfortified plant food contains any significant amount of active vitamin B-12.” “The only reliable vegan sources of B12 are foods fortified with B12 (including some plant milks, some soy products and some breakfast cereals) and B12 supplements.” (Jack Norris, RD)

These foods are fortified:

  • Vitamin B12 fortified non-dairy milk (soy milk, almond milk, rice milk, etc.)
  • Vitamin B12 fortified vegetarian meats
  • Vitamin B12 fortified energy bars
  • Certain brands of breakfast cereals (cheerios, etc)
  • Red Star Vegetarian Support Formula

Disclaimer: Do not take this information as medical advice.  I am not an expert in nutrition, but I cite many credentialed doctors and registered dietitians.  Please see a qualified healthcare professional for advice.

Norris, Jack, RD. “What Every Vegan Should Know about Vitamin B12.” Vegan Health. Vegan Outreach, n.d. Web. 03 Aug. 2013. <>.

Craig, Winston J., PhD, MPH, RD, and Ann R. Mangels, PhD, RD, LDN, FADA. “Position of the American Dietetic Association: Vegetarian Diets.” Journal of the American Dietetic Association 109.7 (2009): 1266-282. Print.

Mangels, Reed, PhD, RD. “Vitamin B12 in the Vegan Diet.” The Vegetarian Resource Group. N.p., n.d. Web. 03 Aug. 2013. <>.

Norris, Jack, RD. “Vitamin B12: Are You Getting It?” Vegan Health. Vegan Outreach, n.d. Web. 03 Aug. 2013. <>.