Recommended Dosage for B12: Vegan Nutrition with Dina Aronson, M.S. R.D.

Dina Aronson, MS, RD is a vegan dietitian whose specialties include chronic disease prevention, vegetarian/vegan nutrition, and lifestyle management. She is the founder and director of VeganRD.com, a nutrition consulting company. Active in many vegetarian nutrition organizations, Dina was the recipient of the American Dietetic Association's Recognized Young Dietitian of the Year Award in 2002.

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I attended a talk given by Brenda Davis recently - really exciting stuff! However I think I may have misunderstood what she said about B12 requirements. I understood her to say we needed 20mcg per day, but this figure is not mentioned in Becoming Vegan or Defeating Diabetes. Can you please confirm how much B12 we need per day, and at what age levels? Thanks very much! -Janet

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Dear Janet,
I'm glad you enjoyed Brenda's talk! I'm not sure where the 20 micrograms comes in, but here's the scoop. The Recommended Dietary Allowances for vitamin B12 are (numbers are in micrograms):

Infants
0-6 months 0.4
7-12 months 0.5

Children
1-3 years 0.9
4-8 years 1.2

Males and Females
9-13 years 1.8
14-18 years 2.4
19-30 years 2.4
31-50 years 2.4
51-70 years 2.4
> 70 years 2.4

Pregnancy
All ages 2.6

Lactation
All ages 2.8

As you can see, the recommended vitamin B12 intakes are 2-3 micrograms per day for most people. But these are not necessarily the numbers we should strive for! These numbers represent amounts that are enough to ensure that we do not become deficient in vitamin B12. However, cutting-edge research has shown that optimal intakes of vitamin B12 are actually higher--more in the range of 5-10 micrograms per day. Therefore, to ensure not only adequate but optimal intake of vitamin B12, vegans should strive for:

3 micrograms per day from fortified foods in 2 or more meals
or
10 mcg per day from supplements
or
2000 mcg per week from supplements

Disclaimer: The advice given here is for eductional purposes only. You should not use this information to diagnose or treat a health problem or disease without consulting with a qualified health care provider.

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