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X Fact
July 24, 2020
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How a Sandwich Spread Helped Scientists Discover the Cause & Treatment of Pernicious Anemia

In 1928, Dr. Lucy Wills (1888-1964), an English hematologist traveled to Mumbai, India to investigate macrocytic anemia, prevalent in pregnant textile workers. She found that the anemia was prevented by adding yeast to the diet and in 1931 published a paper showing that a popular spread introduced in 1902 by the Marmite Food Company that contained brewer's yeast cured this particular anemia. Marmite has high concentrations of folate and vitamin B12.

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Macrocytosis is a term used to describe red blood cells that are larger than normal. Anemia is when you have low numbers of properly functioning red blood cells in your body. Macrocytic anemia, then, is a condition in which your body has overly large red blood cells and not enough normal red blood cells. Different types of macrocytic anemia can be classified depending on what’s causing it. Most often, macrocytic anemias are caused by a lack of vitamin B-12 and folate. Macrocytic anemia can also signal an underlying condition.

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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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