This contributes to the absorption mechanism of oral vitamin B12, which does not depend only on intrinsic factors, but the absorption can be done through passive diffusion
B12 is Found Naturally in Animal Products Vitamin B12 is produced almost exclusively by bacteria and is concentrated in animal foods: beef and lamb (highest density), fish and shellfish (especially salmon, trout, clams), dairy, and eggs
The focus is not just on treatment, but on helping people understand why a specific option fits their needs
[1] Because intrinsic-factor-dependent uptake in the distal ileum can be absent in conditions such as autoimmune gastritis, pancreatic insufficiency, or bariatric surgery, the intramuscular or subcutaneous route bypasses gastrointestinal barriers and reliably restores serum concentrations