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Vitamin B1, thiamine


Vitamin B1 helps the body to produce energy, and it is involved in the metabolism of amino acids, lipids, alcohol, and glucose. Vitamin B1 is also needed in the function of the heart, nervous system, and muscles. It is also called thiamine.

We get thiamine from the following foods: whole-grain bread, eggs, poultry, pasta and rice, pork, fish, legumes (such as black beans and soybeans), seeds, and nuts. Foodstuffs are supplemented with vitamin B1 in many countries as a way of preventing vitamin B1 deficiency.

Vitamin B1 reserves are scarce, and deficiency can easily emerge in a few weeks if there is no intake of vitamin B1. People who consume high amounts of alcohol are the most significant risk group, as alcohol prevents the absorption of vitamin B1 and interferes with sugar metabolism, in which vitamin B1 is involved. Other risk groups include the malnourished and those with intestinal diseases. The need for vitamin B1 can be as much as triple during pregnancy.

When should vitamin B1 levels be measured?

Vitamin B1 levels should be measured when suspecting vitamin deficiency.

Vitamin B1 deficiency can cause:

  • loss of weight and appetite
  • disorientation
  • memory loss
  • muscle weakness
  • heart problems.

In addition, vitamin B1 deficiency can cause Wernicke–Korsakoff syndrome, which most commonly affects people with high alcohol consumption, causing stinging and numbness of the arms and legs, severe memory loss, confusion, and disorientation.

What does a vitamin B1 test measure?

Measuring the level of vitamin B1 in the blood indicates whether the body has enough vitamin B1.

The test does not give the reason for the deficiency, namely, whether vitamin deficiency is caused by insufficient intake or an absorption disorder.

Normally, the result is:

Reference values:

  • 28 - 85 μg/l

Please contact your physician or other healthcare professional if you suspect an illness or need help interpreting the results.

The reference values of this examination have changed 11.10.2021. You will find your own result's reference values from My LOUNA in touch with the graph. Read more about defining reference values.

Excessive intake of vitamin B1 is rare. It can be caused by eating products with high amounts of supplemented B vitamins. These include nutritional supplements.

Deficiency can be caused by limited or insufficient diet, malnutrition, drugs that interfere with the absorption of vitamin B, gastric bypass surgery, high alcohol consumption, and chronic diseases with effects on the absorption of nutrients (coeliac disease).


Fasting is not required

This examination does not require fasting