An activist brought to my attention the article B12 Deficiencies in Vegans? Not True! at Flaming Vegan. I guess I’m naive about what vegans are saying about vitamin B12, but I was very surprised to read the article and the comments, and so I posted a response below it. It’s mostly about seaweed as a source of vitamin B12.
Another reader brought my attention to a page on vegan triathlete Brendan Brazier’s site, Lesson 2: [url=Lesson 2: High Net-Gain Nutrition]High Net-Gain Nutrition[/url]. On that page, he claims that miso is a source of vitamin B12. In fact, the two studies that have measured vitamin B12 in miso have found none.
Brazier also claims that chlorella is “the best source of B-12!” Two studies have found vitamin B12 analogues in batches of chlorella while one study found practically none. This could mean that the B12 analogues in the two studies that found it were there from contamination, which means it cannot be relied upon. More importantly, Chlorella has not been tested to see if it improves vitamin B12 status in humans. The track record of other seaweeds that were once considered a source of B12 has not been good, so there is reason to be skeptical of chlorella as well. Thus, chlorella is far from the best source of vitamin B12.
Citations for the miso and chlorella studies can be found in B12 in Tempeh, Seaweeds, Organic Produce, and Other Plant Foods.
As an aside, Brazier lists romaine lettuce and arugula as sources of calcium. According to the USDA, one cup of shredded romaine has only 15 mg of calcium, making it a poor source. One cup of arugula has 32 mg of calcium, making it a somewhat better source, but still not very good.
I sent Mr. Brazier a note through his contact form on May 5 in an attempt to alert him to these issues and did not get a response. As of today, this information is still on his website so I thought it was appropriate to let readers know they should not rely on this information and continue my attempt to spread the word to the vegan community about reliable sources of vitamin B12.