I'm Dr. Alan Goldhamer. For maintaining health, I do not recommend much in the way of supplementation. Health is mostly a result of healthful habits, but there is one vitamin that I believe healthy vegans should either supplement with on a regular basis or test their levels every two years.
Reason for Concern
The concern over whether a vegan diet can ensure adequate vitamin B12 is a question that vegans must face squarely. For those who have been philosophically committed to the notion that a strict vegan diet can and will give you everything you need, I have a warning: Vitamin B12 is a material essential for your optimal health, and a strict vegan diet may not be providing this vitamin at adequate levels for you. There are legitimate scientific questions about how best to assure adequate B12 intake.
Overview of vitamin B12
Vitamin B12 was first isolated in 1948. It is derived exclusively from bacteria. Since that time, research has established that vitamin B12 is required for a number of important functions, including the synthesis of thymidylate—a substance necessary for DNA synthesis. In addition, vitamin B12 is necessary for chemical interactions that make possible the recycling of methyl folate. If a person is deficient in vitamin B12, this recycling process can be disrupted. The deficiency then can result in problems identical to those caused by a folate deficiency, such as the death of hematopoietic cells in the bone marrow. Vitamin B12 deficiency also can result in inadequate myelin synthesis. Myelin is the fatty substance that insulates some nerves, allowing for normal neurological communication. If myelin synthesis is impaired, neurological problems can result. Difficulties can include numbness in the hands and feet, unsteadiness, poor muscular coordination, and even cognitive deficits such as confusion, mental slowness, and memory problems. The best way to measure B12 is to order a methylmalonic acid or homocysteine test as elevations of these tests are more sensitive indications of b12 status. A serum B12 can be a misleading and unreliable assessment of your B12 status.
Finding a good source
In a more primitive setting, human beings almost certainly would have obtained an abundance of vitamin B12 from the bacterial “contamination” of unwashed fresh fruits and vegetables—regardless of their intake of animal products. Human vitamin B12 deficiency is very unlikely to occur in such a setting. Only very small amounts of dietary vitamin B12 are needed because our bodies do a fabulous job of recycling this essential nutrient. A person living in the ancestral environment regularly would have consumed fresh fruits and vegetables that were not consistently, fastidiously cleaned—as we routinely do today. Our current unusual degree of hygiene is useful for combating many health threats—but may leave long-term, strict vegans vulnerable to the potential problem of vitamin B12 deficiency.
My offer to you
Although there are many fine sources of supplemental B12, the best appears to be methylcobalamin, and we have selected Pure Encapsulations which is a reliable company making many excellent vegan products. One 5000mcg bottle of liquid B12 will last 4 months. I would like to offer you free shipping for a 4-month supply of vitamin B12.