Thiamine

• Alternative Names

  Vitamin B1; Diet - thiamine; Deficiency - vitamin B1

• Function

  Thiamine (vitamin B1) helps the body cells convert carbohydrates into energy. It is also essential for the functioning of the heart, muscles, and nervous system.

• Food Sources

  Thiamine is found in fortified breads, cereals, pasta, whole grains (especially wheat germ), lean meats (especially pork), fish, dried beans, peas, and soybeans.

  Dairy products, fruits, and vegetables are not very high in thiamine, but when consumed in large amounts, they become a significant source.

• Side Effects

  A deficiency of thiamine can cause weakness, fatigue, psychosis, and nerve damage. Thiamine deficiency in the United States is most often seen in those who abuse alcohol (alcoholism). A lot of alcohol makes it hard for the body to absorb thiamine from foods. Unless those with alcoholism receive higher-than-normal amounts of thiamine to make up for the difference, the body will not get enough of the substance. This can lead to a disease called beriberi.

  In severe thiamine deficiency, brain damage can occur. One type is called Korsakoff syndrome. The other is Wernicke's disease. Either or both of these conditions can occur in the same person.

  There is no known poisoning linked to thiamine.

• Recommendations

  The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for thiamine:

  Infants

  • 0 - 6 months: 0.2 milligrams per day (mg/day)
  • 7 - 12 months: 0.3 mg/day

  Children

  • 1 - 3 years: 0.5 mg/day
  • 4 - 8 years: 0.6 mg/day
  • 9 - 13 years: 0.9 mg/day

  Adolescents and Adults

  • Males age 14 and older: 1.2 mg/day
  • Females age 14 to 18 years: 1.0 mg/day
  • Females age 19 and older: 1.1 mg/day

  Specific recommendations for each vitamin depend on age, gender, and other factors (such as pregnancy). Adults and pregnant or lactating women need higher levels of thiamine than young children.

  The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.

• References

  Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2007.

  Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, PantothenicAcid, Biotin, and Choline. National Academy Press, Washington, DC, 1998.

  Mason JB. Vitamins, trace minerals, and other micronutrients. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 237.

Review Date: 3/16/2009

Reviewed By: Linda Vorvick, MD, Family Physician, Seattle Site Coordinator, Lecturer, Pathophysiology, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.