From what vegetables can I get enough B12 vitamin?
No vegetable is a good source of vitamin B12. The only exception might be fermented soy product (Tempeh) since bacteria synthesise vitamin B12 as a by-product. Seaweed and spirulina could be none animal option but again the amount of B12 in these product are insufficient to provide enough for healthy people.
I have heard that body can store B12 for a long time(years),I'm vegan for about 8 years and my diet otherwise is preety good but I don't take any vitamin suplemments,none.Am I in trouble?
Yes the body can store B12 for years but eventually you might run out if your diet does not have sufficient amount of vitamin added. Also, you could have sufficient amount of B12 which provided to you by your gut microflora, depending the species present. You probably do not have to take B12 everyday but once week would be a good idea. Alternatively you could take yeast extract based product such as Marmite and Vegemite.
I wonder how good the yeast extract we use to make media for human consumption.
If you are working out, or do work that is physical, you will not regret the B-12 (or a B-complex) increase. Energy stays higher, muscles not as tired and/or sore. The body will regulate the level you need, so don't worry about higher than RDA %.
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