Vitamin B1

Other names Thiamine

Vitamin B1

Vitamin B1 from the diet or supplements is crucial to brain functioning. Some people supplement vitamin B1 to improve brain functioning, but is supplementation effective for cognitive enhancement? Read on to find out what the science says.

This nootropic has no healthy human placebo-controlled studies that meet our inclusion criteria. Negative side effects can occur if used carelessly, so make sure you’re aware of the risks of Vitamin B1.


Read about the effects of Vitamin B1 in relation to the amount of evidence we've found

Why do people use vitamin B1?

People who self-experiment with vitamin B1 often state they use it to improve their:

  • Energy
  • Memory
  • Focus
  • Mood
  • Sociality
  • Learning

There is a lack of solid scientific evidence for the effectiveness of vitamin B1 for any of these purposes, especially in healthy humans.

Can vitamin B1 supplements improve energy levels for healthy people?

Vitamin B1 supplementation may improve reaction time and subjective energy levels in healthy people, but more research is needed before it can be known with certainty whether it is effective or not.

Two months of daily supplementation of 50mg vitamin B1, which is a very high dose, in 120 healthy young adults resulted in improved subjective ratings of "clearheaded", "composed", and "energetic". [1] The authors of the study concluded the following:

"The taking of thiamine had no influence on memory but reaction times were faster following supplementation. These influences took place in subjects whose thiamine status, according to the traditional criterion, was adequate." [2]

High-dose Vitamin B1 supplementation improved fatigue after stroke in three people, but these findings are not easily transferable to healthy humans and are not that useful in our quest to find an answer to whether energy level improvements in healthy people.

Can vitamin B1 supplements improve cognitive performance for healthy people?

It is not known whether vitamin B1 is an effective cognitive enhancer for diseased people or healthy humans. The optimal dose for cognitive enhancement in healthy people is unknown, and doses used in studies vary by several orders of magnitude which makes informed self-experimentation very hard.

A super-high mega-dose of vitamin B1 (3-8g/day) resulted in mild beneficial effects in people with Alzheimer's. [3]

In 2001, the authors of a Cochrane review (an especially reputable sort of systematic review) concluded that there was not enough evidence on the potential benefits of vitamin B1 for cognition in Alzheimer's disease. [4]

Vitamin B1 deficiency can definitely lead to severe cognitive impairment. [5]

Vitamin B1 deficiency can impair cognitive performance, but whether supplementation of vitamin B1 in healthy people who are not deficient can improve cognition is not known.


The legality and side effects of Vitamin B1


Frequently asked questions about Vitamin B1


Studies conducted on the effects of Vitamin B1 in healthy humans

Last updated Saturday, June 10, 2023