Rankings / Essentials — Vitamins & Minerals
Vitamin B1 (thiamine)
Essentials · Vitamin
Tier A+
Bottom line
Read Off Label grades Vitamin B1 (thiamine) as A+ (8.4/10) based on strong evidence, high benefit magnitude, and a low-risk safety profile.
Diuretics, alcohol, glucose loads, and bariatric surgery deplete thiamine fast.
Typical use: 1. — OTC; Rx.
What this is
Diuretics, alcohol, glucose loads, and bariatric surgery deplete thiamine fast. Empirical IV thiamine before any glucose load in suspected refeeding/alcoholic encephalopathy is standard ICU practice. Benfotiamine (lipid-soluble analog) has better tissue penetration and is the form used in diabetic neuropathy trials.
Mechanism
Cofactor for pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, transketolase — central to glucose oxidation and the pentose phosphate pathway; required for branched-chain amino acid metabolism
Dose & route
1.1-1.2 mg/day RDA; 50-100 mg/day for at-risk groups (alcohol use, bariatric surgery, hyperemesis); benfotiamine 150-600 mg/day for diabetic neuropathy
Citations
- https://pubmed.ncbi.nlm.nih.gov/30694669/
- https://pubmed.ncbi.nlm.nih.gov/22183257/
- https://ods.od.nih.gov/factsheets/Thiamin-HealthProfessional/
Links go to the source. If a link is dead or you want something re-checked, let me know.
Common questions
- Does Vitamin B1 (thiamine) work?
- Read Off Label rates the evidence for Vitamin B1 (thiamine) as Strong and the benefit magnitude as high, producing an overall grade of A+ (8.4/10). Diuretics, alcohol, glucose loads, and bariatric surgery deplete thiamine fast.
- Is Vitamin B1 (thiamine) safe?
- Vitamin B1 (thiamine) has a low risk profile in published human data. Legal status: OTC; Rx (IV/IM for Wernicke). This is not medical advice — see the disclaimer.
- What is the typical dose for Vitamin B1 (thiamine)?
- 1.1-1.2 mg/day RDA; 50-100 mg/day for at-risk groups (alcohol use, bariatric surgery, hyperemesis); benfotiamine 150-600 mg/day for diabetic neuropathy
- How does Vitamin B1 (thiamine) work?
- Cofactor for pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, transketolase — central to glucose oxidation and the pentose phosphate pathway; required for branched-chain amino acid metabolism
This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.