That often looks like: improved mood more follow-through with workouts less fatigue after work better motivation If fatigue has been your most significant issue, this is often when the benefits are most apparent
Metformin (for diabetes), proton pump inhibitors (such as omeprazole or esomeprazole), and H2 blockers (such as famotidine) can all reduce B12 absorption over time
[3] Prolonged therapy can unmask or exacerbate benign prostatic hyperplasia, raise prostate-specific antigen, worsen untreated obstructive sleep apnoea and is associated in some observational studies with a small but controversial increase in cardiovascular events, underlining the necessity for baseline and periodic monitoring of PSA, lipids and cardiovascular risk factors
For reliable background on vitamin B12, see the NIH fact sheet: Vitamin B12 - Health Professional Fact Sheet
Lancet 2021 Phase 1b (cagri + sema) Enebo et al., n=96, 20 weeks