Vitamin B1 (Thiamine)
An essential B vitamin for converting carbohydrates into energy.
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What it is
Thiamine is a B vitamin that helps turn carbohydrates into energy and supports nerve function. It's found in whole grains, pork, and legumes.
How it works
Thiamine (B1) helps convert carbohydrates into cellular energy and supports normal nerve and heart function. Because the body stores little, a steady intake matters, and deficiency shows up quickly in energy-demanding tissues.
What it's been studied for
Used to correct or prevent thiamine deficiency and support energy metabolism.
What the evidence shows
Thiamine is essential, and correcting a deficiency (common with heavy alcohol use or malnutrition) resolves real problems. In people who aren't deficient, extra thiamine doesn't boost energy.
Who should consider it
Deficiency is mainly a concern with heavy alcohol use, malnutrition, or certain medical conditions. For most people a normal diet covers it, so routine supplementing offers little beyond correcting a shortfall.
Amounts commonly studied
Daily needs are small (around 1-1.2 mg); therapeutic doses are higher and used under guidance.
How to take it
Daily needs are small (about 1-1.2 mg); therapeutic doses are higher and used under guidance. Benfotiamine is a fat-soluble form marketed for nerve health. It's water-soluble and taken with or without food.
Forms & absorption
Thiamine HCl or mononitrate; benfotiamine is a fat-soluble form marketed for nerve health.
Food sources
Whole grains, pork, legumes, nuts, seeds, and fortified cereals and breads.
Safety & interactions
Very safe and water-soluble, with excess excreted. Few interactions.
Myths & what it won't do
Myth: B1 supplements boost energy in healthy people. Reality: they only resolve fatigue caused by an actual deficiency. Myth: everyone needs extra. Reality: a varied diet meets needs for most.
Common questions
- Who's most likely to be low in B1?
- Heavy drinkers, people with malnutrition, and some with digestive or metabolic conditions — situations where supplementation is genuinely useful.
- What is benfotiamine?
- A fat-soluble derivative of thiamine marketed for nerve support; it's absorbed differently than standard thiamine.
- Is it safe?
- Very safe and water-soluble, with excess excreted.
The amounts listed here are what published research has used — not a prescription or a recommended dose for you. Confirm anything you plan to take with your own healthcare provider, especially if you take medications, are pregnant or nursing, or have a health condition.
Related goals
Research on Vitamin B1 (Thiamine)
Recommendations on this page are informed by published research. This is educational information, not medical advice.
- Martin PR, Singleton CK, Hiller-Sturmhöfel S. The role of thiamine deficiency in alcoholic brain disease. Alcohol Res Health. 2003;27(2):134-142. View study →