Can eosinophilic esophagitis cause vitamin B12 deficiency?

Can Eosinophilic Esophagitis Cause B12 Deficiency?

Eosinophilic esophagitis (EoE) itself does not directly cause vitamin B12 deficiency, but the dietary elimination therapies used to treat EoE can lead to B12 deficiency if dairy products are eliminated without proper nutritional replacement. 1

Direct Disease Effects

• EoE as a disease entity does not impair gastric acid production or intrinsic factor secretion, which are the primary mechanisms for B12 malabsorption 1
• The esophageal inflammation and eosinophilic infiltration in EoE are localized to the esophagus and do not affect the stomach or terminal ileum where B12 absorption occurs 1
• No published evidence links untreated EoE directly to vitamin B12 deficiency 2

Indirect Risk Through Treatment

The real risk for B12 deficiency in EoE patients comes from the dietary elimination strategies used for treatment:

Dairy Elimination Risk

• Dairy products are a primary dietary source of vitamin B12, along with protein, calcium, phosphorus, and vitamin D 1
• Milk is one of the most commonly eliminated foods in EoE treatment, included in 2-food, 4-food, and 6-food elimination diets 1
• The 2-food elimination diet (milk and wheat) achieves 43% remission, 4-food diet achieves 60% remission, and 6-food elimination diet achieves 79% remission 1

Compounding Factors

• Patients with concurrent food allergies or those following vegan/plant-based diets face even higher risk of nutritional deficiencies when dairy is eliminated 1
• The restrictive nature of elimination diets can lead to multiple concurrent nutritional deficits if not properly managed 1

PPI-Related B12 Deficiency Risk

If EoE patients are treated with proton pump inhibitors (PPIs), they face an additional independent risk for B12 deficiency:

• PPIs reduce gastric acid production, which impairs vitamin B12 release from food proteins and reduces intestinal absorption 1, 3
• Long-term PPI use (≥2 years) at doses >1.5 pills/day is associated with increased risk of diagnosed B12 deficiency (OR: 1.95; 95% CI: 1.77,2.15) 1
• Patients taking B12-containing multivitamins may still develop deficiency with long-term PPI use, as supplementation may not fully prevent PPI-induced malabsorption 3
• PPIs are used in 30-50% of EoE patients as part of treatment 4, 5

Clinical Recommendations

Strong recommendation: All EoE patients undergoing dietary elimination therapy must receive support from an experienced dietitian throughout the elimination and reintroduction process 1

Monitoring Strategy

• Assess baseline nutritional status before initiating elimination diets, particularly when dairy will be eliminated 1
• Monitor for B12 deficiency in patients on long-term PPI therapy, especially those with additional risk factors 3
• Consider B12 supplementation proactively in high-risk patients (those eliminating dairy, on long-term PPIs, or with concurrent dietary restrictions) 1, 3

Common Pitfall

• The most critical error is initiating elimination diets without dietitian involvement, which significantly increases the risk of nutritional deficiencies including B12 deficiency 1
• Assuming that over-the-counter multivitamins will prevent deficiency in patients on long-term PPIs—they may not be sufficient 3