Biotin (vitamin H) blood test in Chiswick

What the test measures

Biotin is a water-soluble B vitamin that acts as a helper for enzymes involved in breaking down fats, carbohydrates and proteins. It is found in eggs, liver, nuts, seeds, salmon and some vegetables, and gut bacteria make a little too. A true deficiency is uncommon in the UK, but it can occur with long-term poor diet, alcohol misuse, some anti-seizure medicines, eating large amounts of raw egg whites, or rare inherited enzyme problems.

Signs of deficiency can include thinning hair, a red scaly rash around the eyes, nose and mouth, brittle nails and tiredness. Many people also take high-dose biotin supplements for hair and nails, and this matters because large amounts can interfere with some laboratory tests, including certain thyroid and heart tests, giving misleading results.

The price includes the blood sample at our Chiswick clinic, analysis at the Randox accredited laboratory, a practitioner review of your result and a GP feedback report on request.

Who it is for

• You follow a restrictive diet and want to check your biotin status.
• You have thinning hair, brittle nails or a rash around the face and want to look at possible causes.
• You take an anti-seizure medicine long term and your practitioner has suggested checking.
• You take high-dose biotin and want to know your level before other blood tests.
• You drink heavily or have a condition affecting absorption.

Understanding your result

Your report shows the laboratory reference range. A low level supports a possible deficiency, and your practitioner will look at your diet, medicines and digestive health for an explanation. A high level is almost always due to supplements. Biotin is not known to be toxic, but a high level is important because it can distort the results of other immunoassay tests, so you may be advised to pause supplements before further testing.

Hair and nail changes have many causes, including iron, thyroid and hormonal factors, so a biotin result is a prompt for discussion, not a diagnosis.

Preparing for your test

No fasting is needed. If you take a biotin supplement, follow the advice we give at booking, as the timing of your last dose affects the result. If you are having other tests on the same visit, such as thyroid hormones, stopping biotin for at least 48 hours beforehand helps avoid interference, but only if this is safe for you.

Iron and thyroid problems are common causes of hair thinning, so our iron and ferritin tests and thyroid tests are worth considering. You can also view every blood test and price in Chiswick.

Questions

How much is a biotin blood test in Chiswick?

The Biotin (Vitamin H) test costs £249 at Omnia Lifestyle in Chiswick. It covers the blood sample, accredited laboratory analysis, a practitioner review of your result and a GP feedback report if requested.

Can biotin supplements affect my other blood tests?

Yes. High doses can interfere with some immunoassays, including certain thyroid, hormone and heart tests, making results look falsely high or low. Always tell anyone testing your blood that you take biotin.

Will biotin help my hair grow?

Biotin can help when hair loss is caused by a deficiency, but there is little evidence that it helps people who already have enough.

Is biotin deficiency common?

No. It is rare in people eating a varied diet, which is why the test is most useful when there is a specific reason to suspect it.