Vitamin B1 (Thiamine)

What is vitamin B1 (thiamine)?

Vitamin B1, also known as thiamine, is a water-soluble vitamin that plays a central role in the body's energy metabolism and nervous system function. The biologically active form in the body is thiamine pyrophosphate (TPP), also known as thiamine diphosphate (TDP), which is the form most often analyzed in blood tests.

Thiamine functions as a cofactor in several enzymatic processes that are crucial for carbohydrate metabolism and the production of energy (ATP). Vitamin B1 deficiency can therefore affect both the brain, muscles and heart.

Synonyms and analysis names

Vitamin B1 can occur under several different names in the laboratory world:

• Thiamin
• Vitamin B1
• Thiamine pyrophosphate (TPP)
• Thiamine diphosphate (TDP)
• B-Thiamin pyrophosphate

It is common to analyze the active form (TPP/TDP) in blood, as it better reflects the body's functional status of the vitamin.

What function does vitamin B1 have in the body?

Vitamin B1 is necessary for several important biological processes:

• Energy production – participates in the breakdown of carbohydrates and the production of ATP
• Nervous system function – important for signal transmission between nerve cells
• Heart function – affects the energy supply of the heart muscle
• Cognitive function – contributes to normal brain function and memory

Because the brain is particularly dependent on glucose as an energy source, it is extra sensitive to thiamine deficiency.

Why is vitamin B1 analyzed?

Analysis of vitamin B1 (thiamine) may be relevant if a deficiency is suspected or if symptoms can be linked to impaired energy metabolism or neurological effects.

Common situations where analysis may be relevant:

• Long-term fatigue and lack of energy
• Neurological symptoms such as tingling, numbness or memory impairment
• Suspected malnutrition or malabsorption
• Alcohol abuse or alcohol dependence
• Follow-up of nutritional status in chronic disease

What can cause low levels of vitamin B1?

Thiamine deficiency is uncommon in Sweden in terms of the population as a whole, but can occur in certain risk groups. Low levels can affect both the nervous system and heart function.

Common causes of thiamine deficiency include:

• Alcohol abuse (reduced absorption and storage).
• Malnutrition or a one-sided diet.
• Malabsorption (e.g. in intestinal diseases).
• Increased need, for example during pregnancy or illness.

Serious deficiency can lead to the disease beriberi, which can affect both the nervous system ("dry beriberi") and the heart ("wet beriberi"). In severe cases of deficiency, especially in people with alcohol dependence, Wernicke-Korsakoff syndrome can develop – a serious neurological condition that affects memory, coordination and consciousness.

What can high levels of vitamin B1 cause?

High levels of vitamin B1 are uncommon and are rarely seen as a clinical problem. Since thiamine is water-soluble, excess is normally excreted in the urine.

Elevated levels can sometimes be seen with:

• Dietary supplements with high doses of vitamin B1
• Parenteral nutrition or treatment with vitamin supplements

High values ​​usually have no negative clinical significance.

Reference values ​​for thiamine pyrophosphate

Reference values ​​may vary between laboratories depending on the analysis method.

Blood (TDP/TPP):

Approximately 70 – 180 nmol/L (may vary between laboratories)

It is important to interpret the value in relation to symptoms and clinical picture.

Risk groups for thiamine deficiency

Certain groups have an increased risk of developing a deficiency of the vitamin B1:

• People with alcohol dependence.
• Elderly people with reduced nutritional intake.
• People with chronic diseases.
• Patients after bariatric surgery.
• People with malabsorption.

Vitamin B1 (thiamine) is crucial for the body's energy production and the function of the nervous system. Deficiency is uncommon in the normal population but can have serious consequences in risk groups, especially in alcohol-related problems. Analysis of thiamine, often in the form of thiamine pyrophosphate (TPP), can provide important information about the body's nutritional status and should be interpreted together with symptoms and other clinical findings.