Long-term use of medications that block stomach acid production has been found to be associated with vitamin B12 deficiency, according to a recent study published in the Journal of the American Medical Association. Vitamin B12 deficiency can lead to dementia, nerve damage, anemia, and other medical complications.

Stomach acid is required to separate B12 from food proteins so that it can be absorbed by the body. Due to this, researchers wanted to investigate the possibility of stomach acid blockers interfering with the absorption of B12. Acid-suppressing medications are among the most widely prescribed medications in the United States. Proton-pump inhibitors (PPIs) are the most common, with histamine 2 receptor agonists (H2 receptor agonists) also widely used.

“Patients who took PPI medications for more than two years had a 65 percent increase in their risk of B12 deficiency,” noted Douglas Corley, MD, PhD. “Higher doses also were associated with an increased risk compared with lower doses.” H2 receptor agonists also had a negative impact on B12 levels, though not as pronounced as PPIs.

“This researcher raises the question of whether people who are taking acid-depressing medications long term should be screened for vitamin B12 deficiency,” said Corley. “It’s a relatively simple blood test, and vitamin supplements are an effective way of managing the vitamin deficiency, if it is found.”

If avoidance of long-term use of acid-suppressing medications is possible—usually via diet and lifestyle modifications and the use of digestive enzymes—please consider it. If it’s not possible, be sure to supplement with B12 as well as probiotics, digestive enzymes, and omega-3 oils.