Thiamine

Thiamine (Vitamin B1)
Also known as: Vitamin B1, Benfotiamine
Vitamin & Mineral

Content by: OpenSupplement Editorial Team  |  Medical review: pending  |  Last updated: April 13, 2026

Evidence ★★★☆☆3/5
Best for
Cognition
Typical dose100-300 mg benfotiamine/day
SafetyNo significant concerns
Onset4–8 weeks
Cost$5-10/mo
References2 studies cited

TL;DR

  • Vitamin B1, essential for glucose metabolism and nerve energy

  • Low evidence for cognitive decline (outside of deficiency)

  • Benfotiamine is the superior fat-soluble form for nerve protection

  • Critical for heavy alcohol users and those with high sugar intake

  • Excellent safety profile

  • Cost: ~$5-10/month

  • Best for: Diabetic neuropathy support, alcohol recovery, metabolic health

What it is

Thiamine was the first B-vitamin discovered. It is the 'spark plug' of the cell, required to turn sugar into energy. The brain and nerves are incredibly sensitive to thiamine deficiency because they are so energy-hungry.

Modern diets high in refined sugar and alcohol 'burn through' thiamine rapidly. Benfotiamine is a special, fat-soluble form of thiamine that reaches the nerves much better than standard B1, making it a favorite for treating nerve damage.

What the research says

Cognitive declineRelevance: Low
Evidence
2.5/5
Onset speed
2/5
Typical dose: 100-300 mg benfotiamine/day

Severe B1 deficiency causes 'Korsakoff Syndrome' (severe memory loss). Evidence. Some research suggests that mild, chronic B1 deficiency may contribute to Alzheimer's, as Alzheimer's brains show reduced thiamine-dependent enzyme activity. Benfotiamine Trial. A small trial showed that Benfotiamine improved cognitive scores in MCI patients over 12 months. It's a promising 'niche' brain supplement. [1][2]

DISCLAIMER: The information on this page is for educational purposes only and has not been evaluated by the Food and Drug Administration. This content is not intended to diagnose, treat, cure, or prevent any disease. Consult a qualified healthcare professional before using any dietary supplement, especially if you are pregnant, nursing, taking medication, or have a medical condition.

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Thiamine on Amazon

$5-10/mo (estimated)
See on Amazon

Safety

Extremely safe. There is no known toxicity level for thiamine. It is well-tolerated even at high doses.

Interactions

None significant. It is very safe to take with other medications.

Dosing

Standard Dose: 100-300 mg daily. Form: Use Benfotiamine for better nerve and brain penetration.

Cost

Cheap. $5-10 per month.

The bottom line

If you eat a lot of sugar, drink alcohol regularly, or have nerve pain, thiamine (specifically Benfotiamine) is an essential metabolic 'safety net.'

References

  1. NIH Fact SheetCognitive declineSource
  2. RCTCognitive declinePubMed

Sources for this page include published meta-analyses, systematic reviews, and NIH dietary supplement fact sheets. All claims reflect the evidence as of early 2026.

This is not medical advice. Consult your healthcare provider before starting any supplement, especially if you take medications.