Also indexed as: Thiamin, Thiamine
Vitamin B1 is is a water-soluble vitamin needed to process carbohydrates, fat, and protein.
Every cell of the body requires vitamin B1 to form the fuel the body runs on—adenosine
triphosphate (ATP). Nerve cells require vitamin B1 in order to function normally.
Vitamin B1 has been used
in connection with the following conditions (refer to the individual
health concern for complete information):
Who is likely to be deficient?
A decline in vitamin B1 levels occurs with age, irrespective of medical
condition.1 Deficiency is most commonly found in alcoholics, people with malabsorption conditions, and those eating a very poor
diet. It is also common in children with congenital heart disease.2 People with chronic fatigue syndrome may also be deficient in
vitamin B1.3 4 Individuals undergoing regular kidney dialysis may
develop severe vitamin B1 deficiency, which can result in potentially fatal
complications.5 Persons receiving dialysis should discuss the need for vitamin B1
supplementation with their physician.
How much is usually taken?
While the ideal intake is uncertain, one study reported the healthiest people consumed more
than 9 mg per day.6 The amount found in many multivitamin supplements (20–25 mg) is more than
adequate for most people.
Vitamin B1 is nontoxic, even in very high amounts.
Are there any side effects or interactions?
Vitamin B1 works hand in hand with vitamin
B2 and vitamin B3. Therefore,
nutritionists usually suggest that vitamin B1 be taken as part of a B-complex vitamin or other multivitamin supplement.
Are there any drug
Certain medicines may interact with vitamin B1. Refer to drug interactions for a list of those medicines.
1. Wilkinson TJ, Hanger HC, George PM, Sainsbury R. Is thiamine
deficiency in elderly people related to age or co-morbidity? Age Ageing
2. Shamir R, Dagan O, Abramovitch D, et al. Thiamine deficiency in
children with congenital heart disease before and after corrective surgery. JPEN J
Parenter Enteral Nutr 2000;24:154–8.
3. Heap LC, Peters TJ, Wessely S. Vitamin B status in patients with
chronic fatigue syndrome. J R Soc Med 1999;92:183–5.
4. Grant JE, Veldee MS, Buchwald D. Analysis of dietary intake and
selected nutrient concentrations in patients with chronic fatigue syndrome. J Am Diet
5. Hung SC, Hung SH, Tarng DC, et al. Thiamine deficiency and unexplained
encephalopathy in hemodialysis and peritoneal dialysis patients. Am J Kidney Dis
6. Cheraskin E, Ringsdorf WM, Medford FH, Hicks BS. The
“ideal” daily vitamin B1 intake. J Oral Med 1978; 33:77–9.