sublingual vs injection b12 Which Is Better? B-12 vs. Vitamin B-12 Pills Efficacy of sublingual versus oral
Description
Recent B12 supplementation, even over-the-counter preparations, can artificially elevate serum levels and mask deficiency

The Confirmatory Antibody Tests If the initial results point to a B12 deficiency, the investigation gets more specific

& Harrison, P

Proton pump inhibitors (acid blockers) and over-the-counter non-steroidal anti-inflammatory agents can change the environment of the GI tract predisposing to nutrient deficiencies Unfortunately, that isnt an exhaustive list, but it does give you a pretty good idea of why you should be concerned about your vitamin B12 levels
