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Trusted to do 100,000+ tests and consultations per month.
Trusted to do 100,000+ tests and consultations per month.
Selenium Blood Test

 


SELENIUM BLOOD TEST

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£109.00
£109.00 - £109.00
£109.00
£109.00 - £109.00
1 BIOMARKER
5 DAYS
INSTRUCTIONS
FAQ

A selenium blood test measures the level of selenium, an essential trace mineral, in your bloodstream. It helps detect deficiencies or excess levels that may be associated with symptoms like fatigue, hair loss, weakened immunity, or nerve-related issues.

Simple and accurate blood test from a laboratory you can speak to.



STEP 1 - CHOOSE YOUR SAMPLE COLLECTION OPTION
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SELENIUM BLOOD TEST OVERVIEW

A selenium blood test measures the level of selenium, an essential trace mineral, in your bloodstream. It helps identify whether you have too little, often due to poor nutrition or absorption issues, or too much, which can occur from over-supplementation or environmental exposure.

The test is typically used when symptoms like fatigue, hair loss, or neurological changes need further investigation and other causes have been ruled out.

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SELENIUM BLOOD TEST

While the body needs only a small amount, both too little and too much selenium can lead to health problems. This test is usually ordered when there are symptoms that might suggest selenium imbalance, such as fatigue, hair loss, brittle nails, or neurological changes, particularly when other common causes have been excluded.

From a medical perspective, the test is most relevant for people with suspected nutritional deficiencies, gastrointestinal disorders affecting absorption (like Crohn’s disease), or those taking supplements that may lead to excess intake. It’s also sometimes used when investigating symptoms of possible trace mineral toxicity.

Though not a routine test, it can offer valuable insight when a patient’s symptoms or medical history suggest a potential selenium imbalance.

1 BIOMARKER

  1. METALS

    - Selenium

  2. UPGRADE

    Need more biomarkers? Add this to our Electrolytes Blood Test

  1. TURNAROUND TIME

    We are extremely fast, with some results available within hours and others within a working day or less, from the time your sample is in our lab. However, this is not a guarantee and should not be taken as such. This is the guideline turnaround time that can be shorter or longer.


    THIS IS NOT A GUARANTEED TURNAROUND TIME.


    We are extremely proud of our very short turnaround times and a very efficient laboratory processes, you will start receiving results as soon as they are available and have completed clinical validation.


    Whilst we accommodate the shortest of time scales, with some results available within hours, for this particular test the usual turnaround time is: 5 working days.

  1. WILL I HAVE A GENERAL EXPLANATION OF MY RESULTS?

    Yes, our doctors put a huge amount of effort into your online Health Dashboard, which will have explanations of what each biomarker is, the normal reference ranges and what it means if you are outside of them.


    This service is included in the price of all our tests.

  1. CAN I SEE A GP TO DISCUSS MY RESULTS?

    Yes, usually the same or next day.


    One Day Tests has a fantastic clinical team of consultants and GPs. Once you have your results you can book an online video consultation to discuss your results.


    Our clinical team consists of practicing NHS and private GPs, who work closely with our laboratory and can tell you what your blood test results mean for you. Having an integrated laboratory and GP services makes your health journey seamless and extremely efficient.


    This service is not included in the price of the test, it is charged separately, should you wish to book it.

DOCTOR'S COMMENTS

Hi, I am Dr. Adam Staten and here's my view on this test as a GP and Clinical Director at One Day Tests.

DR. ADAM STATEN - GP VIEW AND RED FLAG SYMPTOMS

From a GP’s perspective, a selenium blood test is a helpful diagnostic tool in specific cases where symptoms and history point toward a possible trace mineral imbalance. We might consider it if a patient presents with unexplained fatigue, hair thinning, nail changes, or neurological symptoms, particularly when more common causes like thyroid dysfunction or iron deficiency have been ruled out. It's also relevant for patients with gastrointestinal conditions that affect nutrient absorption or those receiving long-term nutritional support.

While not part of routine blood work, the selenium test becomes important when assessing the impact of dietary habits, supplement use, or chronic illness on a patient's overall health. Detecting abnormal levels early allows us to intervene appropriately, whether that means adjusting supplements, addressing absorption issues, or referring for further specialist input.

Red flag symptoms for the Selenium Blood Test

Your Results and Health Dashboard

The results of your Selenium Blood Test will be emailed to you as a secured PDF file, ready for your GP and will also be uploaded to our Health Dashboard area of the website. It’s a unique and powerful tool, powered by our in-house clinical analysis research, to match your biomarkers across test panels and symptoms, as well as provide clinical commentary on all individual biomarkers you tested for.

The health dashboard will also provide "panel level" commentary - a birds eye view of the biomarkers that were tested. This feature allows you to view your test results and clinical commentary, and compare them to previous results, giving you a clear understanding of how your health is progressing.

By using the Health Dashboard, you can identify changes in your biomarkers and make necessary adjustments to your lifestyle. This added value is immense, as it empowers you to monitor your health and make informed decisions about your well-being.

It's free and is available with all of our tests.

SAVE ON CONTINUOUS MONITORING WITH OUR SUBSCRIPTION PLAN

The best way to look after your health is to do so regularly. This is easy to do with our continual monitoring plans which give you a discount on future blood tests. You choose the frequency and we'll do the rest.

When you purchase a subscription, we will deliver your home test kits or allow you to book appointments in line with your chosen frequency. You will be able to track your biomarkers over time in our powerful Health Dashboard, where results will be automatically updated for you. There is a minimum of 3 tests with any subscription, after which you can pause/restart/cancel at any time.

SPECIAL INSTRUCTIONS

Hi, I am Stefania Brown, I am the Laboratory Manager at One Day Tests and here are the lab's special requests for the Selenium Blood Test.

SPECIAL INSTRUCTIONS

Fasting is not required for a selenium blood test.

Clinic appointment - how to prepare for the Selenium Blood Test

If you are coming into one of our clinics for the test, this is what you need to do before you arrive:

  • Read the instructions in the SPECIAL INSTRUCTIONS section
  • Drink plenty of water about an hour before the appointment.
  • Avoid coffee/tea/energy drinks. Water is good!
  • That’s it! We’ll do the rest.

We look forward to receiving your sample in our lab!

WHY CHOOSE US?

Hello! My name is Dr. Vinesh Mistry, I am part of the GP team here at One Day Tests and here is why you should trust us to test your blood.

QUICK AND ACCURATE RESULTS DIRECT FROM A LABORATORY.

We run our own regulated laboratories and our own accredited clinics. We manufacture our own approved home sample collection kits. Your results are looked after by our fantastic clinical governance team and our super-talented biomedical science team.

When you book your test with us - you book directly with the lab. This means accuracy and responsible duty of care, direct access to the provider and extremely fast turnaround times.

Finally, our customer services rock! You can ask the lab a question any time or you can speak to a real human. You can email us on hello@onedaytests.com or give us a call on 0127 309 2844.

FREQUENTLY ASKED QUESTIONS

Hi, I am Lana Nela, Lead Nurse, and here is what we are frequently asked about this test.

FREQUENTLY ASKED QUESTIONS

Here are some of the most frequently asked questions about the Selenium Blood Test.

What symptoms could indicate a selenium imbalance?

Selenium imbalances can cause a range of symptoms that often overlap with other conditions. A deficiency may lead to fatigue, hair loss, brittle nails, a weakened immune system, or fertility issues. In more severe cases, low selenium can affect thyroid function or cause muscle weakness and cognitive changes. On the other hand, too much selenium, often from excessive supplementation, can result in nausea, a metallic taste, garlic-like breath odour, and nerve or gastrointestinal symptoms.

Because these signs can be subtle or mistaken for other health issues, a selenium blood test can be useful when more common causes have been ruled out, especially if the person has a restricted diet, gut absorption issues, or takes high-dose supplements.

What causes high or low selenium levels?

Low selenium levels are most often caused by poor dietary intake, chronic digestive disorders (like Crohn’s disease or coeliac disease), or long-term intravenous nutrition without proper supplementation. Certain regions with selenium-deficient soil can also contribute to lower intake through food. People who avoid meat, seafood, or grains may also be at higher risk of deficiency.

High selenium levels are usually due to overuse of supplements, as it’s rare to reach toxic levels through diet alone. Some health products contain selenium in high concentrations, and long-term use without monitoring can lead to toxicity. Identifying the cause is key to managing selenium levels safely.

How is a selenium blood test different from other nutrient tests?

The test provides a snapshot of current selenium status, but it’s most accurate when combined with clinical assessment and, in some cases, repeat testing or nutritional review. Because selenium is involved in so many essential functions, from thyroid activity to immune defence, the test can offer important clues when other results are inconclusive.

WHY HAVE THE TEST?

Hi, I am Nader Eldarf, I am a Biomedical Scientist in our laboratory and here is why it's important to take this test.

  1. WHY HAVE THE SELENIUM BLOOD TEST?

    A selenium blood test is important because selenium plays a crucial role in many bodily functions, including immune response, thyroid hormone metabolism, and protection against oxidative stress. Both deficiency and excess can lead to health problems, low levels may contribute to fatigue, weakened immunity, or infertility, while high levels can cause symptoms like hair loss, nerve damage, or gastrointestinal issues.



    By measuring selenium levels, the test helps identify imbalances early, guiding treatment decisions such as dietary changes, supplementation, or stopping excess intake. This is especially important for people with absorption disorders, those on restrictive diets, or anyone taking high-dose supplements.

IS THIS TEST RIGHT FOR YOU?

Hi, I am Sandeep Patel, I am the Laboratory Director at One Day Tests. Here are the symptoms that you may wish to address with this test.

  1. IS THE SELENIUM BLOOD TEST RIGHT FOR YOU?

    A selenium blood test might be right for you if you're experiencing symptoms that could be linked to a selenium imbalance, such as fatigue, hair loss, brittle nails, or neurological changes, and other common causes have been ruled out.

    It’s also relevant if you have a condition that affects nutrient absorption (like Crohn’s disease or coeliac disease), are on long-term parenteral nutrition, or take high-dose supplements that could lead to excess selenium.

  1. SYMPTOMS AND TAGS

    Fatigue, Memory issues and Tremors

WHY ARE BLOOD TESTS IMPORTANT?

Health monitoring is very important, you are in charge of your health - look after it.