Researchers observed a 65% increase in the risk of B12 deficiency on patients who took PPI (proton pump inhibitors, acid suppressing medications) for more than 2 years. They also discovered that higher doses of PPI corresponded with higher risk of B12 deficiency
A study published in the Journal of American Medical Association (2013) investigated the health records (including diagnoses, pharmacy orders and lab results) of 25,956 patients with Vitamin B12 deficiency and 184,199 patients with normal levels of B12 over a period of 4 and 1/2 years. Researchers observed also that another related class of acid-depressing medications called histamine-2-receptor agonists (H2RAs) had an impact on Vitamin B12 levels, which was less pronounced than the one caused by PPI but was still significant.Stomach acid enables vitamin B12 absorption amongst many other nutrients, but when these acids are suppressed the consequences could be health threatening.
Vitamin B12 deficiency, left untreated can increase risk of dementia, nerve damage, anaemia and other medical conditions which could be irreversible in some cases.