Proton Pump Inhibitors and Vitamin B12 Deficiency
In a recent article published in Aliment Pharmacol Ther, Feb, 2008, it was brought to the attention of the healthcare community that patients on proton pump inhibitors such as Omeprazole may suffer from B12 deficiency despite normal serum levels of B12. This underestimates the prevalence of the deficiency and leaves many patients untreated.
However, B12 elevates two markers called homocysteine and methylmalonic acid, which can be measured to determine the true status of B12 activity. This particular study aimed at determining the true prevalence of B12 deficiency and whether acid suppression by proton pump inhibitors (PPI) caused it. Sixty-one ‘hypersecretors’ on PPI therapy were studied and followed for up to 18 years to determine pharmacological and clinical efficacy and safety of PPI therapy in general, particularly regarding B12 status.
Results showed that of 61 patients, 10% had low serum B12. Additional tests uncovered B12 deficiency in 31% of the 41 still-available patients, despite normal serum B12. B12 replacement normalized homocysteine and methylmalonic acid, supporting the diagnosis. The conclusions of the study were that B12 deficiency was more frequent by 29% than could be determined by measuring serum B12 alone and that there was not enough acid suppression to explain this deficiency.
Again, clearly more studies are needed. But, one thing is clear, individuals on PPI therapy need to be monitored for B12 status by looking at methylmalonic acid levels in particular as opposed to relying on serum B12 levels alone.
About the Author
Kathy Shattler received her Master of Science degree from Michigan State University in E. Lansing Michigan in Human Nutrition. Her twenty-two years of practice includes holding positions as a Lecturer, Chief Clinical Dietitian and Program Manager. Kathy is the Founder of Nutri-Care Consulting and is currently the Nutrition Director of www.CEU4U.COM, an online continuing education management company for Registered Dietitians and Dietetic Technicians.
