Individuals seeking to support their health by following a vegan (total vegetarian) diet often face a multitude of advice-laden comments from friends, family, and even their physicians. Typically, these communications suggest that vital nutrients are commonly deficient in the vegan diet. The old standby, "But you can't get enough complete protein without meat," recently has been joined by, "But you need fish oil for essential fatty acids." Such advice is, of course, incorrect, being little more than the "deficiency paranoia" of the ill-informed. Knowledgeable people have few serious health concerns about the adoption of a vegan diet. Vitamin B12, however, is the rare exception.
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, we 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. In this article, we will examine carefully the "B12 Question," and offer suggestions that we believe may prove to be helpful.
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.
Most people obtain the majority of their vitamin B12 intake from animal products. Although most people associate vitamin B12 deficiency with vegan diets, the majority of cases occur among people who regularly consume animal products. So, it should come as no surprise that vitamin B12 deficiency can occur in vegans.
Finding a good source
There is no dispute that we must be concerned about obtaining adequate vitamin B12. The question is, "Do vegans need to resort to eating animal products, and expose themselves to the well-documented health risks of these foods, in order to maintain adequate vitamin B12 reserves?"
Before attempting to answer the above question, we need to consider whether animal products are naturally necessary for humans to maintain vitamin B12 reserves. This raises two important questions: "Have animal products always been the sole purveyor of vitamin B12 in the human diet?" and, "Are they the best source of this nutrient?"
We believe that the answers to both of these questions are likely to be "no." Upon reflection, we should note that 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.
A little goes a long way
Even in the modern environment, with our fastidious food cleanliness, a person consuming a vegan diet may never experience the need for vitamin B12 supplementation. Even the small amounts of B12 commonly found in the nodules of organically-grown root vegetables, and the small amounts produced by the bacteria in our own mouths, may be enough to sustain many of us. A very little of this substance can go a long way. For those who switch to a vegan diet, for example, there are usually stores of B12 in the liver that can last for several years, or even decades. However, the doctors at the TrueNorth Health Center work with a large number of vegan patients every year, and we have documented dozens of cases of vitamin B12 deficiency, all of which corrected with supplementation. Although many of our patients are understandably resistant to the idea that they might need supplementation, we urge them to test periodically for this possible deficiency, and to take appropriate action when indicated. We also recommend that all pregnant and lactating women include a reliable source of vitamin B12 to ensure the nutritional adequacy of their milk supply.
Keeping it simple
Our advice is straightforward: If you adhere to a vegan diet, we recommend that you either (1) have yourself tested for vitamin B12 deficiency every two years, or (2) ensure a reliable source of vitamin B12. The most appropriate test for evaluating B12 status is the blood or urine test for methylmalonic acid (MMA). Elevated MMA is currently our best tool for detecting vitamin B12 deficiency, and is considered to be superior to testing for serum B12 directly. We recommend that if you choose to avoid all animal products, fortified foods, and supplements, periodic testing for elevated MMA is indicated. The laboratory utilized by the TrueNorth Health Center charges less than $100 for this test. An alternative and less costly screening blood test is Homocysteine.
If you would like to avoid MMA testing, we then would recommend that you include a reliable source of vitamin B12 in your diet. For people without a deficiency, 1000 mcg. per day (vegan capsule or liquid) should be sufficient to maintain most individual's serum B12 levels and body reserves. For those with a known deficiency, a consultation with a Hygienic physician is indicated. However, in most cases, this problem can be readily addressed with oral supplements without resorting to the injection of vitamin B12.
We believe that a diet that includes animal products, although adequate in vitamin B12, poses many health risks that are best avoided.
Playing it safe
Unlike many unfounded "deficiency problems" associated with the vegan diet, the issue of potential vitamin B12 deficiency is real. However, B12 deficiencies, when they occur at all, take years to develop, so don't take our cautioning like the blaring of a five-alarm fire. If you choose to consume a diet consisting exclusively of whole natural foods, as we recommend, it is possible that, partly as a result of our modern cleanliness, you may become B12 deficient.
We recommend that you test periodically to assure that this does not become a problem. If it does, consult with a doctor who can advise you on how to take a responsible course of action.
With a bit of prudence, you can have the best of both worlds: all of the benefits of a vegan diet and none of the problems with animal products.