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X Fact
August 3, 2020
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A More Accurate Way of Measuring Vitamin B12 Status than a B12 Blood Level

It is important to know that once vitamin B12 is taken up by the cells in the body, it is converted into either A.) methylcobalamin, after receiving a methyl or single carbon (-CH3) group from active folate or converted into B.) adenosylcobalamin, which is an essential cofactor in converting methylmalonyl-CoA into succinyl-CoA which is needed for energy production of the cell. Methylcobalamin transfers its methyl group to homocysteine (Hcy) and converts it into methionine, which is critical for reading genes and methylation reactions. It is not important for the purposes of this X Fact to understand the chemistry, but what is important it that if there is not enough vitamin B12 inside the cells to participate in these two important functions, then the substance that is not being converted begins to accumulate and spill over into the blood and urine. Elevated homocysteine (Hcy) can be detected when there is a deficiency of either Vitamin B12, Folate or B6, whereas elevated methylmalonic acid (MMA) is a very sensitive test of vitamin B12 deficiency at a cellular level, and can often identify vitamin B12 deficiency long before clinical symptoms are recognized.

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Methylcobalamin is vitamin B12 that has a methyl group (-CH3) attached to it. This typically occurs once vitamin B12 is absorbed into the cell and accepts the methyl group from methyltetrahydrofolate (the active form of folate). Once B12 is 'methylated' by folate, it transfers this single carbon methyl group to homocysteine which converts it into the amino acid, methionine. This takes place in the cytoplasm of the cell.

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Adenosylcobalamin is formed inside the mitochondrium (the energy producing apparatus within the cell) when adenosine is transferred from ATP (the molecule that carries energy) to vitamin B12. This form of B12 is an essential cofactor to the enzyme that converts methylmalonyl-CoA to succinyl-CoA which is needed for energy production in the Kreb's cycle.

Who Wrote This X Fact
Jonathan Bortz MD
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Jonathan’s background as a practicing diabetes specialist for 15 years and 17-year career developing nutritional prescriptive products for the pharmaceutical industry has contributed to his ability to understand nutrients, how they work and why they are important.

Over the years he has acquired broad and in-depth knowledge in minerals, essential fatty acids and other nutrients, but has special expertise in Vitamin B12 and choline metabolism. He is often asked to speak at national and international venues to articulate why B12, folate and choline are so important to gene function, brain development, liver and cardiovascular health. He applies pharmaceutical standards to nutrient science and has developed a unique ability to translate complicated concepts into simple promotional messages that resonate with practitioners and consumers. He has developed dozens of innovative nutritional products, of which many are category leaders in the US. Jonathan obtained his medical degree from the University of the Witwatersrand Medical School in South Africa and did his fellowship in Endocrinology at Washington University in St. Louis, MO.

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