Vitamin B12 and Vitamin B12 + Metformin: one depletes the other
Each entry’s own grades, side by side. A grade says how strong the evidence is for one outcome — it does not rank one entry over the other.
Compound or practice
Vitamin B12
Non-negotiable for plant-based diets and older adults — deficiency is quiet until it's neurological.
Grade A3 graded outcomesrevised Jul 10, 2026
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
Interaction
Vitamin B12 + Metformin: one depletes the other
Long-term metformin lowers B12 in up to a third of users — test annually.
Grade B0 graded outcomesrevised Jul 10, 2026
Assembled by the app from other entries in this library. It adds no evidence of its own — follow the links to the entries it draws on.
Graded in both
Outcomes are matched by name. Two entries can describe the same outcome in different words, so one listed further down may still be graded in the other.
No outcome has the same name in both entries. They may still overlap under different wording — read the two lists below.
Graded only in Vitamin B12
- Correcting deficiency / anemia Large effectEvidence grade A
- Neuropathy (early deficiency) Moderate effectEvidence grade A
- Energy in replete people Trivial effectEvidence grade D
Graded only in Vitamin B12 + Metformin: one depletes the other
None — every outcome it grades is graded in both.
Conditions
Only in Vitamin B12
- Pernicious / macrocytic anemia ImprovesEvidence grade A
- Cognitive decline No clear effectEvidence grade C
Only in Vitamin B12 + Metformin: one depletes the other
None.
What each entry says about the other
- Vitamin B12 + Metformin: one depletes the other’s entry · Watch with: About Vitamin B12
Both columns are read from the entries as they stand in this library. A comparison is not advice to take either one, and it is no substitute for a clinician who knows the person.