Vitamin B1 (thiamine) blood test in Chiswick

What the test measures

Thiamine, or vitamin B1, helps cells release energy from carbohydrates. The brain, nerves and heart use a lot of energy, so they are among the first parts of the body to be affected when thiamine runs low. The body holds only small reserves, which means a few weeks of poor intake or high losses can be enough to reduce levels.

Good sources include wholegrains, pork, peas, beans, nuts and fortified breakfast cereals. Low thiamine is most often linked to long-term heavy drinking, which reduces absorption, but it can also follow prolonged vomiting, eating disorders, weight-loss surgery or long courses of some diuretics. The test is usually carried out on whole blood and measures the active form of the vitamin. The price includes the blood sample taken at our Chiswick clinic, analysis at the Randox accredited laboratory, a review of your result with an Omnia practitioner and a GP feedback report on request.

Who it is for

• You drink alcohol heavily or regularly and want to check your thiamine status.
• You have had bariatric surgery or a long period of vomiting or very poor eating.
• Your diet relies heavily on refined foods such as white rice or white bread.
• You notice tingling or numbness in your feet, muscle weakness or poor memory and want to look at nutritional causes.
• You take long-term diuretics and your clinician has suggested checking B vitamins.

Understanding your result

Your report shows your thiamine level next to the laboratory reference range. A low result supports thiamine deficiency, especially when it fits your history and symptoms, and your practitioner will discuss diet, alcohol and whether you should see your GP about treatment. A level within the range is reassuring, although it is interpreted alongside how you feel.

Sudden confusion, unsteady walking or unusual eye movements in someone at risk of thiamine deficiency can be a medical emergency and need same-day assessment through A&E or NHS 111, not a booked blood test. Any result outside the range is a reason to talk things through with your practitioner, not a diagnosis by itself.

Preparing for your test

A fasting sample is often preferred for thiamine, and we will confirm whether you need to fast when you book. Tell us about any B vitamin, multivitamin or thiamine supplements you take, as recent doses can raise the result.

For a broader nutritional picture, our Nutritional and Digestive Health check combines several markers, and the Liver Function Check is often helpful where alcohol is a factor. Browse every blood test and price in Chiswick.

Questions

How much is a vitamin B1 blood test in Chiswick?

The vitamin B1 (thiamine) test costs £179. That includes your sample at our W4 clinic, analysis at an accredited laboratory, a practitioner review and a GP feedback report on request.

What are the signs of low thiamine?

They can include tiredness, irritability, poor memory, tingling or numbness in the hands and feet, and muscle weakness. Severe deficiency can affect the heart and brain, which is why sudden confusion or unsteadiness needs urgent care.

Is thiamine deficiency only linked to alcohol?

No. Alcohol is the most common cause in the UK, but low thiamine can also follow weight-loss surgery, repeated vomiting, eating disorders, very restricted diets and some long-term medicines.

Should I stop my supplements before the test?

Please do not stop anything prescribed. For over-the-counter supplements, let us know what you take when you book and we will advise on timing.