What's the best source of B12?

There are three primary sources of B12 for vegans.

1. Nori (red algae)

2. Chlorella

3. Spirulina

There are two types of B12. There’s a pseudo B12 (B12 analog) and real B12. B12 analog is similar in chemistry to B12, but not similar in function. So if an algae has large amounts of pseudo B12, it can block real B12. In turn, this can cause a serious deficiency.

Unless you’re taking B12 supplements, I do not recommend that you try to get all of your dietary B12 from nori or spirulina. However, chlorella does contain a significant amount of real B12. This is the best source of vitamin B12 for vegans. You need about 6 tablets or one teaspoon of chlorella twice per day.