Spirulina & B12
Spirulina is an excellent source of Vitamin B-12. However, there is some unresolved controversy over exactly how much B-12 it contains. B-12 is essential for normal growth and neurological function; a deficiency causes fatigue and moodiness, and eventually neurological damage. The body does produce its own B-12 and can store it for years, but vegetarians in particular are susceptible to B-12 deficiency.
The richest sources of B-12 are meats – especially organ meats – and dairy foods. Spirulina, fermented foods such as miso, and certain sea vegetables were thought to contain high levels of B-12. However, research into the effects of these foods on B-12 levels in the body and on B-12 deficiency has shown that these foods may actually contain B-12 analogues that do not fulfill the biological requirements of the body.
The Recommended Daily Allowance (RDA) of B-12 for adults is three micrograms. Using the government-approved microbiological assay, Spirulina was found to contain 2.2 micrograms of B-12 per gram. Thus, by taking 3 grams of Spirulina per day (in powder form or by taking six 500 mg tablets) you can get more than double the government approved RDA. To be fair, we must also consider the results of another testing method called a radioassay.
With the radioassay method, a level of 0.4 micrograms of B-12 per gram was found. If we go by the lower radioassay figure, fifteen tablets or two-and-a-half teaspoons of Spirulina powder would provide the RDA. That still makes Spirulina a very good source of Vitamin B-12, containing more than a serving of fish or eggs.
Excerpted the book SPIRULINA: Nature’s Superfood By Kelly Moorhead and Bob Capelli with Dr. Gerald R. Cysewski