Methylcobalamin is produced by taking taking more standard, synthetic forms of B12, such as cyanocobalamin or hydroxocobalamin, and methylating them by adding CH3 (one carbon atom bonded to three hydrogen atoms) to the molecular structure through various chemical processes.
The whole idea of this chemistry is to re-create outside of the body the kind of B12 that is commonly formed inside the body. Methylcobalamin is desirable as a dietary supplement because it is more highly bioavailable than the other forms mentioned above.
One of methylcobalamin’s greatest roles in the body is in support of the methylation of toxic elements. By methylating arsenic, lead, cadmium and mercury containing substances, as well as other toxic materials from food and metabolism, methylation reduces their toxicity and prepares them for excretion.
Although this is just one step in the biochemical process of methylation, it is a critical one. Given that people may struggle with inefficient methylation, supplementing with methylcobalamin helps keep the system running more efficiently.
B12 is not found in plants, which means plant extracts cannot be expected to be sources of B12. It is an animal nutrient that human biochemistry adapted to hundreds of millions of years ago when our ancestors ate termites. We later moved on from insects as our primary protein source to other animal foods, which also contain B12.
The human gut also contains B12-synthesizing bacteria. The presence of these bacteria is an important reason vitamin B12 is provided to those who have been strict vegetarians or vegans all of their lives. The colon contains the greatest number of bacteria where most of our intestinal B12 is produced. However, because B12 is absorbed in the ileum, which lies upstream of the colon, this plentiful source of B12 is not immediately available for absorption, and most gets eliminated. Feces contain large amounts of active B12. Until recently most people lived in close contact with their farm animals, and consumed B12 left as residues by bacteria living on their un-sanitized vegetable foods.
Supplementing our modern lifestyle with B12 becomes important because of:
- Increased exposure to toxic elements as our world becomes more polluted, and as our food sources are either grown with chemicals, or preserved with chemicals.
- Stress and poor immunity that keep metabolic processes working insufficiently at times.
- Processed foods, abundant sugar consumption, and use of antibiotics and other pharmaceutical medications, that have compromised what should be a plethora of good/friendly B12 producing bacteria.
- Extremely sanitized food environments, which is so important in many ways, has created a lack of environmental bacterial B12 sources.
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