Thiamin (B1)

Water-soluble · energy

What does Thiamin (B1) do in your body?

Helps turn carbohydrate into energy and supports nerve function.

What does Thiamin (B1) do?

As thiamin pyrophosphate, it's a coenzyme for key steps that release energy from glucose.

Where does Thiamin (B1) act in the body?

Every cell, especially brain, nerves and heart, which use a lot of glucose.

Which foods contain Thiamin (B1)?

Whole and enriched grains, pork, legumes, seeds, fortified cereals.

How much Thiamin (B1) do adults need?

RDA: 1.2 mg (men), 1.1 mg (women). No upper limit set.

What happens with too little Thiamin (B1)?

Deficiency causes beriberi and, often with heavy alcohol use, Wernicke–Korsakoff syndrome — a serious brain condition.

Can you get too much Thiamin (B1)?

No toxicity known from food or supplements.

What does Thiamin (B1) interact with?

Heavy alcohol use reduces absorption and increases needs.

What is known and unknown about Thiamin (B1)?

Roles in energy metabolism are established.

Evidence & sources

• The adult RDA for thiamin is 1.2 mg (men) and 1.1 mg (women). Evidence: regulatory. Known: Set by the Institute of Medicine (1998). Unknown: — Source: NIH Office of Dietary Supplements, Thiamin — Health Professional Fact Sheet (Current revision).

Connected topics

• Energy Metabolism
• Carbohydrate
• Nerve Signaling
• Alcohol

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.