Best Sources of B12
Vitamin B-12 is the only essential vitamin produced exclusively by bacterial synthesis and is found in the colon of healthy mammals.1 In healthy humans, B-12 is produced in the colon and can be found in saliva,7 but there is no proof that this B-12 is the active vitamin, or is abundant enough to contribute as a reliable source of vitamin B-12. Drinking water, raw home-grown vegetables, fermented foods, fortified soy products, breakfast cereals, faux-meats, nutritional yeast and mushrooms are other possible sources of vegan sourced vitamin B-12, but the reliability of these sources is extremely untrustworthy, unless specifically fortified with the vitamin.8
Tempeh and fermented foods
Tempeh is actually a good source of vitamin B-12 in its home country, Indonesia, however its Western counter-part is not so unless specifically fortified with B-12. While the Balinese street vendor is a viable place for bacteria to synthesis B-12, the sterile, air conditioned western tempeh kitchen is not so. This was discovered by a study in the 1980s, which showed that, oddly, Western-produced tempeh was completely devoid of vitamin B-12.9
The same reasoning can be applied to other fermented foods such as miso, pickled vegetables, sourdough bread and sauerkraut.
Homemade, unpasteurised fermented foods may contain vitamin B-12 but, again, this is not reliable, cannot be tested and should not be considered a dependable source, regardless of studies showing unpasteurised foods having higher vitamin B-12 than pasteurised varieties.10
On a more positive note, while fermented foods may not be a reliable source of vitamin B-12 in the western diet, they do offer vital digestive enzymes to the human body, and thus increase bowel health, potentially improve bowel synthesis of B-12 and boost the immune system.1 So thumbs up to fermented food, and definitely a reason to include them in your every day diet.
Micro and macro algae (sea weed)
Various products claim to having naturally high levels of B-12, and micro-algae is one of them. Spirulina and cholera regularly publicise this, but fail to mention that the levels are not of the vitamin B-12, but of B-12 analogues. Not only are B-12 analogues useless to the human body, they inhibit intestinal absorption of vitamin B-12 from that same food- meaning, if spirulina contains any actual vitamin B-12, the high level B-12 analogues in spirulina inhibit its bio-availability and absorption into the human body.11
In the 1990’s, when 40 vegan foods were tested for levels of B-12 in Japan, only two came back with what was considered to be decent levels- nori and spirulina. Subsequently, B-12 deficient children who were eating a macrobiotic diet were supplemented with nori and spirulina for 6 months, and then tested to compare serum B-12 levels and markers for B-12 deficiency. The results showed that despite raised serum B-12 (indicating good absorption of B-12 from the food) the markers for B-12 deficiency were not at all improved. The study concluded that B-12 found in nori and spirulina was predominantly an unusable analogue, rather than the desired vitamin B-12.12
The delicious cheesy flavoured yeast is a popular accompaniment to vegan cooking, adding delightful elements to nut cheeses, sauces and tofu dishes, and is one of the only foods vegans can rely on for vitamin B-12.
There are two methods of production that result in nutritional yeast being a reliable source of vitamin B-12- either the yeast is grown on a vitamin B-12 rich medium or (more dependably) it is fortified with vitamin B-12 at the end of production1. Not all nutritional yeast contains vitamin B-12, so please check the label carefully, and consume moderately; the recommended daily intake is 2 tablespoons per day.
What is the recommended daily intake for vitamin B-12?
To ensure adequate vitamin B-12 intake the following recommendations have been made for adults over 18 years of age (note; this is to maintain levels, NOT to treat an already existing deficiency);
- Eat 3 micrograms (mcg) of vitamin B-12 from fortified foods, daily, or:
- Take a sublingual supplement of B-12 of 1000 mcg/day
If you are vitamin B-12 deficient
Established deficiency treatment includes intravenous injections or sublingual supplementation. For more detailed information, including dosages for children, pregnant and lactating woman and for various illnesses, visit the Mayo Clinic page on the subject. Please consult your healthcare practitioner for a diagnosis and to receive you the most appropriate dosage for you).
Assessing your vitamin B-12 levels can be done via a routine blood test, and it is a good idea to do this annually, especially if you avoid fortified/processed foods. You can get a copy of the blood tests results, which you may want to take along to your local nutritionist or naturopath to discuss.
A wholesome, well planned vegan diet can provide the nourishment necessary for all life stages, though fortified food/supplements may be essential for certain phases. Possible food sources of vegan vitamin B-12 are unreliable at most, unless specifically fortified, and cannot be considered a source of the vitamin.
Supplementing with sub-lingual vitamin B-12 is affordable, highly effective, easily available and completely necessary for most long-term vegans who have a low intake of vitamin-B12 fortified foods. While some individuals may not like the idea of supplementing a wholesome, unprocessed vegan diet, given the seriously debilitating alternatives, it’s a small compromise to make- until the future presents us with a trustworthy, wholefoods option for plant-based vitamin B-12.
For extra information about B-12 deficiency, its causes, diagnosis methods or treatment, visit this source.