Compound or practice · Supplement
Thiamine (B1)
Small stores, fast turnover — deficiency (beriberi, Wernicke's) is a medical emergency; routine supplementation rarely does more.
- Overall grade
- Grade B
- Last revised
- 2
- graded outcomes
- 0
- references listed
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
1 at grade A · 1 at grade B — 2 graded rows
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Deficiency syndromesEvidence grade A
Beriberi, Wernicke's
Largehigh
- Diabetic neuropathy (benfotiamine)Evidence grade B
Modest symptom relief
Smallmixed
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Studies disagree: Diabetic neuropathy (benfotiamine) (mixed agreement).
The evidence in words
What it is
Thiamine is a water-soluble vitamin with unusually small body stores, so deficiency develops quickly under high-carbohydrate loads, alcohol-use disorder, or malnutrition. Benfotiamine is a fat-soluble derivative with better tissue uptake.
How it works
As thiamine pyrophosphate it is a cofactor for pyruvate dehydrogenase and transketolase — nodes where carbohydrate metabolism feeds the energy and pentose-phosphate pathways. Nervous tissue, heavily glucose-dependent, fails first when it runs out.
What the evidence shows
Grade A for treating deficiency syndromes (beriberi, Wernicke encephalopathy), where prompt thiamine is life-saving and delay causes permanent damage. In replete people, supplementation offers little. Benfotiamine has modest evidence in diabetic neuropathy. Alcohol-use disorder and bariatric surgery are the settings where proactive supplementation matters.
How to use it
Requirement is ~1–1.5 mg/day. At-risk groups (heavy drinkers, post-bariatric) use higher oral doses or, in acute deficiency, parenteral thiamine under care.
Safety & interactions
Very safe; excess is excreted. The risk is missing deficiency, not the supplement.
Bottom line
A quiet essential with a dramatic deficiency. Most people get enough; heavy drinkers, the malnourished, and bariatric-surgery patients should supplement — and acute deficiency is an ER matter, not a capsule.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- At-risk
- Higher oral doses in alcohol-use disorder / post-bariatric; parenteral for acute deficiency.
Related reading
Entries that share this one's tags or conditions.
- Thiamine (B1) for Deficiency syndromesEvidence grade A — Beriberi, Wernicke'sEvidence grade A
- Thiamine (B1) for Diabetic neuropathy (benfotiamine)Evidence grade B — Modest symptom reliefEvidence grade B
- Thiamine (B1): dosage and how to take itHigher oral doses in alcohol-use disorder / post-bariatric; parenteral for acute deficiency.Evidence grade B
- Thiamine (B1): side effects, safety & interactionsVery safe; excess is excreted. The risk is missing deficiency, not the supplement.Evidence grade B
Sources
This entry lists no references of its own.
Last revised . A grade is this entry's reading of the evidence, not medical advice.