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X Fact
August 21, 2020
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Measuring MMA Levels can Detect Vitamin B12 Deficiency Even When a Vitamin B12 Blood Test is Normal

In a study of healthy, older urban residents living in India, vitamin B12 blood levels were found to be low in 16% of the 175 subjects tested. But when the blood was tested for methylmalonic acid (MMA), 55% of the population were found to have a functional vitamin B12 deficiency. MMA is elevated when there is not enough B12 available in the cells for the energy pathway. It is therefor a highly sensitive indicator of cellular vitamin B12 deficiency even in otherwise healthy people, and can be easily measured in the blood or urine.

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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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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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