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Originally published July 28 2009

Vitamin B 12 Deficiency and Metformin Usage Trigger Peripheral Neuropathy

by Melanie Grimes

(NaturalNews) Vitamin B12 is an important nutrient used in the nerves and the blood. Deficiency has now been shown to trigger peripheral neuropathy in diabetes patients who take the drug Metformin. Because B12 is difficult to absorb, many people have deficiencies and are not aware of its effect on their health. B12 is not prevalent in the diet and most people need additional supplementation. The only sources of vitamin B12 are in animal and dairy products. For the over seven million vegetarians, adding B12 to their diet is a necessity.

Metformin, a popular drug given to treat diabetes and insulin resistance, can also cause a B12 deficiency. A recent survey found that 40% of metformin users were deficient in vitamin B12. Three-quarters of those metformin users also displayed the peripheral neuropathy typically found in diabetics. These findings were reported at the American Diabetes Association`s 69th Annual Scientific Sessions in June, 2009. This prompted a recommendation that anyone using Metformin who has peripheral neuropathy be screened for vitamin B12 deficiency.

Vitamin B12 is a water-soluble nutrient. One of its most important functions is to build the red blood cells that carry oxygen throughout the body. Another function is in the nerves, where B12 assists in the firing of nerves, sending important messages from the brain to the body.

B12 deficiency can cause fatigue, low blood pressure, dementia, depression, muscle weakness, hallucinations and vision problems, and tingling in the limbs. Some forms of dementia and Alzheimer`s disease are reversible with proper B12 supplementation. Levels of vitamin B12 just under normal can cause symptoms, even before symptoms of anemia are observed.

To properly digest vitamin B12, stomach acid is required. Stomach acid decreases with aging, and it is estimated that as much as 30% of the population over the age of 50 lacks enough stomach acid to properly digest B12 from food. Gastric cells secrete a substance called intrinsic factor. This substance binds to the B12 to absorb it. If the body doesn`t produce enough intrinsic factor, vitamin B12 deficiency can result.

Toxic colon can also prevent absorption of vitamin B12. Overgrowth of unfriendly intestinal bacteria can cause a B12 deficiency, and a third of adults over the age of 50 are presumed to have this condition as well. Antibiotics can disrupt intestinal flora and trigger an overgrowth. Probiotics in products such a yogurt can help restore a proper digestive environment that would be more conducive to vitamin B12 absorption.

Some people require higher doses of vitamin B12 than others. This group includes pregnant and nursing mothers, people on ulcer medication or those who have pernicious anemia or digestive disorders.

B12 supplements can be given orally or by injection. Recommended dosage is 500 mcg. per day. A simple blood test can be used to diagnose a B12 deficiency. Those taking Metformin are advised to have their B12 levels checked.

About the author

Melanie Grimes is a writer, award-winning screenwriter, medical journal editor, and adjunct faculty member at Bastyr University. She also teaches homeopathy at the Seattle School of Homeopathy and the American Homeopathic Medical College.
A trained homeopath, she is the editor of the homeopathic journal, Simillimum, and has edited alternative and integrative medical journals for 15 years. She has taught creative writing, founded the first Birkenstock store in the USA and authored medical textbooks.
Her ebook on Natural Remedies for the Flu is available at:
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