Vitamin B1 (Thiamine)

Thiamine

Vitamin B1, also called thiamine or thiamin, is one of 8 B vitamins. All B vitamins help the body convert food (carbohydrates) into fuel (glucose), which the body uses to produce energy. These B vitamins, often referred to as B-complex vitamins, also help the body metabolize fats and protein. B-complex vitamins are needed for a healthy liver, skin, hair, and eyes. They also help the nervous system function properly and are needed for good brain function.

All B vitamins are water soluble, meaning that the body does not store them.

Like other B-complex vitamins, thiamine is sometimes called an "anti-stress" vitamin because it may strengthen the immune system and improve the body's ability to withstand stressful conditions. It is named B1 because it was the first B vitamin discovered.

Thiamine is found in both plants and animals and plays a crucial role in certain metabolic reactions. Your body needs it to form adenosine triphosphate (ATP), which every cell of the body uses for energy.

It is rare to be deficient in thiamine, although alcoholics, people with Crohn disease, anorexia, and those undergoing kidney dialysis may be deficient. Symptoms of thiamine deficiency are:

  • Headache
  • Nausea
  • Fatigue
  • Irritability
  • Depression
  • Abdominal discomfort

People with thiamine deficiency also have trouble digesting carbohydrates. This allows a substance called pyruvic acid to build up in the bloodstream, causing a loss of mental alertness, difficulty breathing, and heart damage, a disease known as beriberi.

Beriberi

The most important use of thiamine is to treat beriberi, which is caused by not getting enough thiamine in your diet. Symptoms include:

  • Swelling, tingling, or burning sensation in the hands and feet
  • Confusion
  • Trouble breathing because of fluid in the lungs
  • Uncontrolled eye movements (nystagmus)

People in the developed world usually do not get beriberi because foods such as cereals and breads are fortified with vitamin B1.

Wernicke-Korsakoff syndrome

Wernicke-Korsakoff syndrome is a brain disorder caused by thiamine deficiency. Wernicke-Korsakoff is actually two disorders. Wernicke disease involves damage to nerves in the central and peripheral nervous systems. It is often caused by malnutrition due to alcoholism. Korsakoff syndrome is characterized by memory problems and nerve damage. High doses of thiamine can improve muscle coordination and confusion, but rarely improves memory loss.

Cataracts

Preliminary evidence suggests that thiamine, along with other nutrients, may lower the risk of developing cataracts. People with plenty of protein and vitamins A, B1, B2, and B3 (or niacin) in their diet are less likely to develop cataracts. Getting enough vitamins C, E, and B complex vitamins, particularly B1, B2, B9 (folic acid), and B12, may further protect the lens of your eyes from developing cataracts. More research is needed.

Alzheimer disease

Lack of thiamine can cause dementia in Wernicke-Korsakoff syndrome. So researchers have speculated that thiamine might help Alzheimer disease. Oral thiamine has been shown to improve cognitive function of patients with Alzheimer. However, absorption of thiamine is poor in elderly individuals. More research is needed before thiamine can be proposed as a treatment for Alzheimer disease.

Heart failure

Thiamine may be related to heart failure because many people with heart failure take diuretics (water pills), which help rid the body of excess fluid. But diuretics may also cause the body to get rid of too much thiamine. A few small studies suggest that taking thiamine supplements may help. Taking a daily multivitamin should provide enough thiamine.

Depression

Low levels of thiamine are associated with depression. In one study of elderly Chinese adults, poor thiamine levels were associated with a higher risk of depression.

Dietary Sources

Available Forms

How to Take It

Precautions

Possible Interactions

Supporting Research