The Healthspan Map · Nutrient

Thiamin (B1)

Compiled by Aamir Malik, PhD, Professor of Neuroengineering at Brno University of Technology, from published studies. He is a researcher, not a physician. Last updated 21 August 2026.

Linked to getting too little

Where a shortfall of Thiamin (B1) is linked: 5 sources.In the order the Map holds them: strongest evidence first. That is a statement about the evidence, not about what matters most.
Condition or system	Direction	Strength	Evidence type	What was found	Source
Brain fog & memory	Eat enough of	Strong	Established clinical	Wernicke-Korsakoff syndrome causes confusion, ataxia, ophthalmoplegia and irreversible amnesia (memory loss) if untreated.	NIH ODS / StatPearls – Thiamin (opens in a new tab)
Chronic fatigue / low energy	Eat enough of	Moderate	Review / narrative	Thiamin is central to carbohydrate energy metabolism; deficiency causes fatigue and weakness.	Micronutrients for energy/fatigue review (Tardy 2020) (opens in a new tab)
Peripheral neuropathy	Eat enough of	Moderate	Review / narrative	Thiamine deficiency causes beriberi neuropathy and drives alcoholic neuropathy.	Nutritional & toxic neuropathy (opens in a new tab)
Stress	Eat enough of	Emerging	RCT / trial	Thiamin supports nervous-system energy metabolism; part of the B-complex shown to reduce psychological stress.	High-dose B-multivitamin stress RCT (Ford et al.) (opens in a new tab)
Cardiovascular	Eat enough of	Strong	Established clinical	Wet beriberi causes high-output heart failure with edema, cardiomegaly and tachycardia.	StatPearls – Thiamin (opens in a new tab)

The Healthspan Map is part of Fix the Floor, a book by Aamir Malik. About the book