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X Fact
July 29, 2020
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Is Measuring Blood Vitamin B12 Levels the Best Way to Test for Vitamin B12 Deficiency?

The short answer is no. Because serum vitamin B12 testing is widely available, familiar and relatively inexpensive, it has become the mainstay for assessing B12 status. It is very sensitive in severe B12 deficiency with megaloblastic anemia, but is not particularly sensitive for mild or subclinical deficiency. This is further complicated by the fact that the test has a very broad range that is considered 'normal' by most commercial laboratories. This often results in the lab reporting results that fall close to their lower limit as 'normal' when the individual is deficient. MMA (methylmalonic acid) and Hcy (homocysteine) are much more reliable markers of metabolic B12 adequacy.

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megaloblast[ meg-uh-luh-blast ] An abnormally large, immature, and dysfunctional red blood cell found in the blood of persons with pernicious anemia or certain other disorders.

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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