At one time in history we got all the B12 we needed from soil based probiotics living on the foods we ate and the unfiltered spring water we drank. After the advent of modern farming practices and the industrialization of our ecosystem, these natural sources became an increasingly inconsistent way to provide our bodies with this nutrient.
Currently, almost everybody is supplementing with this vitamin in some form, whether it be consuming foods that are commonly fortified such as milks and cereals or eating livestock which get routinely injected with B12 to ensure their meat contains adequate levels.
Despite being found in many processed foods and animal products, the results of a study published in the American Journal of Clinical Nutrition found that 39% of American adults were deficient in this vitamin (1). Considering that vegans reportedly account for only 1% of the population of America, it’s safe to assume that this is not just an issue for those following a plant-based diet.
Supplements
The three most popular types of supplemental B12 are cyanocobalamin, hydroxocobalamin and methylcobalamin. They can be obtained in various forms including powders, sublingual liquids and lozenges. Oral supplementation is a great measure to prevent B12 deficiency. However, if you have been diagnosed with low blood levels you may want to consider a professionally administered injection as this is still the most proven method for correcting a known B12 imbalance.
1. Cyanocobalamin is one of the most stable, cheap and accessible forms of Vitamin B12. The discovery of this form actually happened by mistake when during an experiment to extract B12 from animal tissues, the sample accidentally became contaminated with cyanide which formed the substance now known as cyanocobalamin.
There’s no need to worry though, as cyanocobalamin releases only miniscule amounts of cyanide when consumed, which the body is readily able to excrete. In fact, cyanide also happens to be found naturally in many foods including apple seeds, bitter almonds and cassava root. The only people who should avoid supplementation with cyanocobalamin are smokers and those with a defective cyanide metabolism.
2. Methylcobalamin is one of the activated forms of B12. It requires no intrinsic factor to be absorbed which is why it’s commonly found in sublingual form. It’s the preferred form of B12 in Japan where this nutrient has been researched extensively. Interestingly, Japan also has a much higher requirement for the minimum blood levels of this vitamin. Their attention to ensuring healthy levels of B12, which plays an important role in cognitive health, may be part of why Japan has some of the lowest rates of Alzheimer’s and age-related dementia of any country in the world.
3. Hydroxocobalamin is said to have a more gradual release in the body than other available forms. Hydroxocobalamin is able to react with cyanide within the body and form cyanocobalamin which can then be excreted. This form might be a good choice for smokers, as It has the ability to help remove the excess cyanide they are exposed to from cigarette smoke (2).
Foods
While Vitamin B12 is a popular topic of discussion, there are also several misconceptions perpetuated about this nutrient. This is due in part to its complexity and its many inactive forms which are found in some foods.
A common impression is that nutritional yeast can produce this vitamin. While certain forms of yeast may grow in close proximity to B12 producing bacteria in the wild, commercially produced dietary yeast is actually enriched with preformed B12.
Another belief is that golden berries contain this elusive vitamin. While golden berries are certainly a nutrient dense fruit they have never been found to contain even a single microgram of Vitamin B12 in any laboratory setting. The common myth that these berries contain the vitamin likely originates from a typo in their description by an online food vendor.
This vitamin cannot be obtained from plants as only bacteria contain the enzymes required for its synthesis. The reason it’s found in various types of seaweeds is due to a symbiotic relationship between the seaweed and natural bacteria (3). All vegan food sources of active B12 are produced by bacterial contamination.
For this reason, cultured foods are often believed to be suitable for supplementing the diet with B12. However, they contain low and inconsistent levels of the vitamin as location, preparation methods and the type of bacteria living on the foods are all confounding factors in the production of the vitamin.
While probiotics, fermented foods and algae products are a great addition to B12 supplementation, they should not be taken in the place of a proper supplement. None of these factors have been adequately demonstrated to replenish low stores of this important nutrient in humans. Even for those who consume animal meat or animal products, supplementation should still be considered as absorption is always an issue to consider and even high levels of animal foods only provide moderate amounts of vitamin B12.
Sources:
1. http://ajcn.nutrition.org/content/71/2/514.long
2. http://www.ncbi.nlm.nih.gov/pubmed/8492341
3. http://www.ncbi.nlm.nih.gov/pubmed/16267554
Madeleine Brown
