The honest answer is that most of the data on BPC-157 comes from preclinical (animal) studies, with limited but growing human evidence
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Practical Takeaways Recognize that intrinsic factor is essential for B12 absorption and cannot be replaced by dietary changes alone Understand that conditions affecting parietal cells can lead to B12 deficiency regardless of dietary intake Consider B12 monitoring in patients with gastric surgery, autoimmune conditions, or chronic PPI use Be aware that oral B12 supplements may be ineffective in intrinsic factor deficiency Appreciate that B12 deficiency can develop slowly and cause subtle neurological symptoms before anemia appears Consider alternative B12 delivery methods (sublingual, injectable) when intrinsic factor deficiency is suspected Related Studies and Research Vitamin B12 Intake From Animal Foods, Biomarkers, and Health Aspects Physiology, Stomach Pharmacology of Proton Pump Inhibitors Use of Proton Pump Inhibitors and Risk of Iron Deficiency: Population-Based Study Episode 25: The Great GERD Mistake - How Medicine Made Heartburn Worse and How to Fix It FAQs What happens if I dont have enough intrinsic factor

While a prescription is not generally required, retail pharmacies like CVS do not reliably stock it for walk-in purchase
Of course, people with a proper vitamin B12 deficiency will see more of a benefit, like improvement with less fatigue, nausea, and irritability