Posted on: February 27, 2016 at 1:51 pm
Last updated: August 11, 2016 at 2:47 pm

Millions of Americans take over-the-counter and prescription drugs to reduce their stomach acid, and don’t realize that they may be creating a vitamin B12 deficiency.

In a recent study published in the Journal of the American Medical Association (JAMA), they set out to measure the prevalence of B12 deficiencies in folks who were taking acid blockers. In the study, they compared 26,000 patients who had a B12 deficiency to about 185,000 patients without a deficiency. (1)


Side Effects of PPIs

Those who took acid blockers in the form of proton pump inhibitors (PPIs) such as Prilosec, Prevacid or Nexium for at least 2 years had a 65% increased risk of developing a B12 deficiency. Those who took a histamine 2 receptor antagonist (H2RAs) such as Tagamet, Zantac or Pepcid had a 25% higher risk of developing a B12 deficiency. (1)

Clearly, if you have to take a medication for acid-related issues, ask your doctor to prescribe a H2RA first, before the commonly prescribed PPI.

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The reason for the strong relationship between B12 and acid blockers is that the stomach requires a strong digestive acid for the body to utilize B12. If the stomach acid is weak as a result of aging, medications, acid blockers, poor digestion or stress, the production of a protein called the intrinsic factor will weaken. Without adequate production of the intrinsic factor, the B12 you get from food will not be made available to the body, resulting in a B12 deficiency.

It is for this reason that B12 shots were so popular for years, until the delivery of B12 directly into the blood through sublingual (under the tongue) pathways were discovered. While B12 reserves can store in the liver for years, new studies are suggesting that when B12 levels are even low-normal there can be numerous related health concerns, such as memory issues, brain fog, fatigue, tingling, numbness, dizziness and difficulty walking. (1,2) In one study, the actual size of the brain or the brain volume actually shrunk in those with B12 deficiency.

That study revealed that supplementation with vitamin B12 may help prevent “shrinkage” of the brain as we age. (2) The study measured 107 people from ages 61-87 for five years with brain scans and MRI’s.

The study found that people who had higher vitamin B12 levels were less likely to experience brain shrinkage compared with those who had lower levels of the vitamin in their blood. None of the people in the study had vitamin B12 deficiency.(2) You do not have to be deficient in B12 to see brain shrinkage. Low B12 levels can put you at risk as well.


Perhaps most exciting was that when B12 was combined with folic acid and B6 there was significant reversal in B12 deficiencies and the brain, mood, memory and energy issues associated with a lack of B12. (3-8)

While the studies suggest numerous benefits from the supplementation of B12, folic acid and B6, we must remember that it was a loss of digestive acid that initiated the deficiency. So, to avoid becoming dependent on a B12 supplement, it’s important to follow the steps to evaluate and reboot your digestive strength.

This article was republished with permission from


Dr. John Douillard
Dr. John Douillard, DC, CAP is a globally recognized leader in the fields of natural health, Ayurveda, and sports medicine. He is the creator of, the leading Ayurvedic health and wellness resource on the web with over 7 million views on YouTube. is evolving the way Ayurveda is understood around the world, with over 1000 articles and videos proving ancient wisdom with modern science. Dr. John is the former Director of Player Development and nutrition expert for the New Jersey Nets NBA team, bestselling author of 7 health books, a repeat guest on the Dr. Oz show, and featured in USA Today, LA Times, and dozens of other national publications. He has been in practice for over 30 years and has seen over 100,000 patients. Dr. John directs LifeSpa, the 2013 Holistic Wellness Center of the year in Boulder, CO.

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