Vitamin B1 / thiamine

Also known as thiamin, thiamine hydrochloride, benfotiamine, vitamin b-1, thiamene.

Last reviewed October 9, 2026 · Jump to references

What is Vitamin B1 / thiamine?

In plain words

Vitamin B1, also called thiamine, is a vitamin the body needs from food. The body turns it into an active form that helps release energy from food and keeps nerves working normally. Researchers study thiamine and related forms for nerve problems and conditions linked to low B1 levels. Its role in correcting deficiency is well established, but benefits from extra B1 in people who already get enough are less certain.

Technical definition

Vitamin B1 (thiamine) is an essential water-soluble vitamin composed of an aminopyrimidine ring linked to a thiazolium ring; thiamine hydrochloride is a salt form, whereas benfotiamine is a synthetic derivative. The body converts thiamine to thiamine diphosphate, a cofactor for enzymes including pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase, supporting energy metabolism rather than acting through a dedicated receptor. Thiamine is available in dietary supplements and medicines, with regulatory classification varying by product and country.

Educational information only. This page does not provide medical advice or determine whether a supplement is appropriate for you. Review supplements with a qualified healthcare professional, especially if you take medication, are pregnant, have surgery scheduled, or have a chronic medical condition.

Evidence by use

Each use is rated on its own. There is no single overall effectiveness score.