Vitamin B12 for Telogen Effluvium
FBased on 13 studies with 8,121 total participants. Results are mixed across studies.
The Bottom Line
Research does not clearly support vitamin B12 supplementation for telogen effluvium — while low B12 is sometimes found in hair loss patients, there is no strong evidence that supplementation helps recovery.
- Mixed results across 13 observational studies
- Some post-COVID hair loss studies measured B12 levels without finding consistent patterns
- No RCTs testing B12 supplementation for telogen effluvium
- Only worth supplementing if a blood test confirms a B12 deficiency
Key Study Findings
Key Statistics
13
Studies
8121
Participants
Mixed
Grade
Referenced Papers
Dosage & Usage
mg = milligrams · mcg = micrograms (1,000× smaller) · IU = International Units
Commonly Used Dosages
- general:
- 2.4 mcg/day
- deficiency:
- 1,000-2,000 mcg/day
Upper limit: No established UL
Dosages Studied in Research
| Dosage | Duration | Effect | N |
|---|---|---|---|
| None | -- | Neutral | 113 |
| None | -- | Neutral | 2851 |
| None | -- | Mixed | 108 |
| not applicable | -- | Mixed | 180 |
| None | -- | Positive | 973 |
| not applicable | -- | Mixed | 467 |
| standard replacement doses | -- | Neutral | 3028 |
| None | -- | Neutral | 100 |
Best taken: With meals; sublingual form can be taken any time
Safety & Side Effects
Reported Side Effects
- ⚠ Generally well tolerated even at high doses
- ⚠ Rare allergic reactions (itching, swelling)
- ⚠ Mild diarrhea or nausea at very high doses
Known Interactions
- ● Metformin (reduces B12 absorption by 10-30%)
- ● Proton pump inhibitors and H2 blockers (reduce B12 absorption)
- ● Colchicine (may reduce B12 absorption)
Tolerable upper intake: No established UL
Always consult your healthcare provider before starting any supplement.
Frequently Asked Questions
Does Vitamin B12 help with Telogen Effluvium?
How much Vitamin B12 should I take for Telogen Effluvium?
Are there side effects of Vitamin B12?
How strong is the evidence for Vitamin B12 and Telogen Effluvium?
Related Evidence
Other ingredients for Telogen Effluvium
Vitamin B12 for other conditions
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products and information on this website are not intended to diagnose, treat, cure, or prevent any disease. The evidence grades presented are based on our analysis of published peer-reviewed research and do not constitute medical advice. Always consult your healthcare provider before starting any supplement regimen.