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Vitamins & minerals health centre

Vitamin B1 (thiamine)

Vitamin B1, also known as thiamine, is a type of B vitamin that is essential for the metabolism of carbohydrates in order to release energy for growth, nerve function and muscle tone.

Vitamin B1 uses

Vitamin B1 has been studied for the prevention and treatment of numerous diseases and conditions. There is some evidence that thiamine supplementation might help prevent the formation of cataracts and kidney disease in those with type 2 diabetes. However, more research is needed.

Vitamin B1 supplements can help people who have an actual deficiency. Low levels of vitamin B1 can cause tingling in the fingers and toes, fatigue, poor concentration, memory problems, mental confusion, poor or lack of appetite and balance problems. However, severe deficiency is rare but can be seen in people with severe malnutrition or as Wernicke-Korsakoff syndrome in people with alcohol dependency. Beri-beri is very rare and the result of thiamine depletion.

Studies have shown that while medical treatment with vitamin B1 is recommended in alcohol dependency - especially to prevent Wernicke-Korsakoff syndrome - the optimal dose is unclear. It was thought that vitamin B1 might improve Alzheimer’s disease but the evidence was inconclusive.

Health claims about vitamins have to be approved by the European Food Safety Authority. It has rejected claims that B1:

Vitamin B1 dose and instructions for use

The NHS says that the adult recommended daily intake of vitamin B1 is 1mg a day for men and 0.8mg a day for women. As vitamin B1 cannot be stored in the body, it should be provided daily through a varied and balanced healthy diet.

Vitamin B1 food sources

Sources of vitamin B1 (thiamine) are:

  • Fresh vegetables and legumes such as beans, peas and peanuts
  • Fresh and dried fruit
  • Eggs
  • Wholegrain breads and fortified breakfast cereals
  • Liver and meat
  • Yeast and yeast products

Vitamin B1 supplement information

Vitamin B1 (thiamine) usually comes in capsules or tablets. It is usually available in combination with other types of vitamin B or in vitamin B complex supplements as well as multivitamin products.

Like any supplement, keep vitamin B1 supplements in a cool, dry place, away from humidity and direct sunlight.

Vitamin B1 warnings

  • Side-effects: There is insufficient evidence regarding the possible health risks of taking high dose vitamin B1 supplements
  • Possible interactions: digoxin, diuretics, antiepileptic drugs (phenytoin), tetracycline, tricyclic antidepressants
  • Do not exceed a daily dose of 100mg vitamin B1 supplement.

WebMD Medical Reference

Medically Reviewed by Dr Rob Hicks on March 03, 2017

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