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How Vitamin B1 Works

Vitamin B1 Deficiency
Numbness, muscle weakness, loss of appetite, and disorders of the nervous system such as irritability, memory loss, and depression, characterize the form of beriberi known as "dry beriberi." In contrast, "wet beriberi" features fluid accumulation, especially in the lower legs. This severe form of the disease interferes with the heart and the circulatory system and can eventually cause heart failure. In childhood, thiamin deficiency stunts growth.

Numbness, muscle weakness, and loss of appetite are all signs of
©2007 Publications International, Ltd.
Numbness, muscle weakness, and
loss of appetite are all signs of dry beriberi.

Almost all elderly people have lower than optimal body levels of thiamin. This may be due to the decline in absorption often seen as people age, or may be due to a restricted diet as people eat less of a variety of foods. People with cardiovascular diseases also have an increased need for thiamin supplementation.

Severe thiamin deficiency seldom occurs today in the Western world, except among alcoholics, who eat little or no food for extended periods of time. They can develop a pattern of neurologic symptoms known as Wernicke-Korsakoff syndrome, involving the nervous system and causing a form of psychosis.

Thiamin deficiency may also occur in people who make poor food choices through ignorance, neglect, or poverty. Diets deficient in thiamin are often deficient in other B vitamins as well, because the B vitamins exist in many of the same foods. Highly processed foods are the main culprit, adding carbohydrates to the diet without the B vitamins needed to process them.

Doses of thiamin two to five times the RDA are used to treat a deficiency. In developed countries, deficiencies are most commonly seen in children receiving chemotherapy; these are easily resolved with supplementation. There are no known toxicity problems with thiamin in large doses.

But deficiencies don't need to be severe to cause problems. Even mildly low levels can bring about delirium or problems with mental function. Thiamin is partially responsible for energy production, including energy for the brain. Without it, the brain just doesn't work as well. It's believed that up to 30 percent of patients who are admitted to mental institutions have a thiamin deficiency.

Thiamin deficiency is rare in the United States, but now you know what to look out for and why thiamin is so important to your health. Make sure you're getting the right amounts of thiamin in your diet to keep beriberi at bay.

Vitamin B1 is just one of many vitamins you need for overall health. Follow these links to learn more about the nutrients your body needs.
  • In How Vitamin B2 Works, read about how B2, or riboflavin, works in concert with its B-complex relatives to metabolize carbohydrates, fats, and proteins.
  • Vitamin B3, or niacin, acts as a coenzyme, assisting other substances in the conversion of food into energy. Learn more in How Vitamin B3 Works.
  • Vitamin B5, or pantothenic acid, can be found in all living cells and in all foods. Learn about its importance to your diet in How Vitamin B5 Works.
  • Vitamin B6 is actually three substances, pyridoxine, pyridoxamine, and pyridoxal, that work to metabolize protein and amino acids. Read more in How Vitamin B6 Works.
  • In How Biotin Works, learn how biotin acts as a coenzyme in several metabolic reactions, such as the metabolism of fats and carbohydrates.
  • To learn about the many vitamins in our diet, how much you should be eating, and where to find them, go to our general Vitamins page.
  • If you're looking for the best prices on B vitamins, click here.

Jennifer Brett, N.D. is director of the
Acupuncture Institute for the University of Bridgeport, where she also serves on the faculty for the College of Naturopathic Medicine. A recognized leader in her field with an extensive background in treating a wide variety of disorders utilizing nutritional and botanical remedies, Dr. Brett has appeared on WABC TV (NYC) and on Good Morning America to discuss utilizing herbs for health.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.