Blood sample collection options

You can choose your preferred collection method when you checkout

Finger prick kit (FREE)

You can do this test at home without the need for a doctor. We'll send you everything you need to collect your sample and post it back to us. And it's all included in the cost. We've put together a video that covers the process, making it easy to check and track your health from home.

Home nurse appointment (+£60)

We'll arrange for a medical professional to visit your home and collect your sample. This is great if you're unsure on how it all works or have trouble collecting a sample. No need to book a doctor's appointment or visit a clinic, we'll send you everything you need to collect a sample and post it back to our labs.

Visit a partner clinic (+£45)

Once you've ordered your test, look out for an email from our phlebotomy partners containing information and a link to book your appointment. We'll send you everything the clinic will need to complete the sample and post it back to our labs.

Organise a nurse myself (FREE)

If none of the above options work for you, you can arrange your own medical professional to collect your sample. There is no additional charge for this. Once you've ordered your test, we'll send you everything you and your chosen medical professional will need to collect a sample and post it back to our labs.

Still unsure how it works? You can find more information on collection methods and the service we provide in our 'How it Works' section.

What gets tested?

6 Biomarkers

Additional biomarkers can be added by personalising this test.

What are biomarkers?

Biomarkers are specific compounds we can detect in your blood sample that reflect different things about your health. Your test will tell you your levels for each of the above biomarkers, and whether they are in a normal range.

About flexible subscriptions

How does a subscription work?

When you purchase this test subscription plan, we will automatically send you another test kit in a few months. Don't worry - you have full control over when this will be, and you can change/cancel it anytime.

When you first purchase this test, you can choose your subscription options in the checkout. We do this, because we recommend taking multiple tests over time to track how your biomarkers change. You'll be charged per test kit (rather than monthly, for example).

Why subscribe to multiple tests?

One test will show you what areas you need to focus on, continued testing will help you learn how your training, diet and lifestyle is impacting your health.

How often should I test?

We recommend a follow up test 3 months after your first test, followed by a test every 6 months depending on your results, but its up to you!

Can I change what's tested in future tests?

Yes, you can tailor/customise subsequent tests (via your app) to focus on just the areas that need improving.

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NHS Lab
Tracked 24
delivery
Personalised
GP advice
Finger prick or venous collection

Blood Test for Tiredness & Fatigue

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Results in 2 working days

6 Biomarkers

Feeling constantly exhausted? The Blood Test for Tiredness & Fatigue helps identify potential causes of low energy, such as iron, vitamin B12, vitamin D, and thyroid imbalances. With a simple at-home finger-prick test, you’ll receive fast, accurate results and expert insights to help improve your energy levels. If you’re tired all the time, this fatigue blood test can uncover key deficiencies and imbalances.

Analysed by
NHS Lab
Tracked 24
delivery
Finger prick or venous collection

£85

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What gets tested?

6 Biomarkers

Blood sample collection options

1 Million+

results delivered

As seen in

As seen in
Active B12 levels in men and women vary by age - Feb 2025 data

Find the cause of your tiredness

A blood test for tiredness can help uncover what’s really behind your low energy, whether it’s low iron, vitamin deficiencies, or thyroid imbalances.

If you’re tired all the time, it could be due to something like anaemia, low B12, or an underactive thyroid, all of which can leave you feeling drained. A simple blood test can highlight these issues, so you know what steps to take, whether that’s adjusting your diet, taking supplements, or speaking to a doctor.

We looked at results from thousands of blood tests and found B12 levels in men and women vary by age. Men’s B12 levels decline with age – with those in the 18-29 age bracket having the highest median levels (99 pmol/L) and those age 60+ having the lowest (81 pmol/L).

The opposite trend is true for women, with those aged 30-39 having the lowest levels (79 pmol/L) compared to the 60+ age group having the highest (102 pmol/L).

A B12 deficiency could be causing your tiredness and fatigue – test today to check your levels.

What this Tiredness & Fatigue Blood Test measures

6 Biomarkers

Active B12

Active B12 measures forms of B12 which are available for direct use by the body. This is a more accurate measure of health than total B12. This vital vitamin has an important role in red blood cell production and helps prevent anaemia. It helps to boost energy, improve mood, and enhances cognitive function.

Vitamin D (25 OH)

Vitamin D is essential for healthy bones, immune function, muscle performance, energy, mood and reducing inflammation. It's primarily produced through sunlight exposure so people in the UK are more prone to deficiency than warmer countries. Vitamin D deficiency can lead to significant tiredness and lethargy.

Ferritin

A ferritin test measures the total level of iron stored in your body. Iron is crucial for energy production, immune function, cognitive health and muscle performance. Low levels can cause fatigue, weakness, low mood and lead to iron-deficiency anaemia. Women are more prone to low ferritin than men due to blood loss during the menstrual cycle.

Thyroid Stimulating Hormone (TSH)

Thyroid-stimulating hormone (TSH) regulates thyroid function by stimulating the production of thyroid hormones T3 and T4, which control metabolism and energy production. Women are more likely to develop thyroid disorders than men. Abnormal thyroid levels impact weight, energy levels leaving you feeling tired and lethargic.

Thyroxine (T4, free direct)

A thyroxine (T4) test is used to check that the thyroid is performing properly. An overactive thyroid can cause too much thyroxine to be released whilst an underactive thyroid can lead to too little. Abnormal levels can impact weight, energy, and mood. Free T4 measures the free or unbound levels of T4.

Triiodothyronine (T3, free)

Triiodothyronine (T3) is the active form of thyroxine (T4). High T3 levels may indicate hyperthyroidism, with symptoms such as fatigue, weight loss, irritability, and increased heart rate. Low T3 levels can suggest hypothyroidism, causing fatigue, weight gain, and muscle stiffness. Free T3 measures the free or unbound levels of T3.

How our Tiredness & Fatigue Blood Test works

Getting the insights you need to improve your health has never been easier.

How it works - collect your sample

Collect your blood sample

Collect a small blood sample at home or have a professional do it for you. Use the included Tracked-24 envelope to send it securely to our lab for analysis.

How it works - view your results

Get fast, accurate results

You’ll receive a detailed report with your personalised scores, insights into your energy levels, including doctor-reviewed comments.

How it works - make improvements

Improve your immune health

Your results highlight areas needing attention, giving you the data to seek further help and improve energy.

Don't let low energy, tiredness and fatigue slow you down. Find your spark with HealthCoach

Powered by cutting-edge technology Forth's market leading app converts blood test results into simple real-world health scores, making insights about your health easy to understand and to act upon

Unlock your health scores

Thyroid health score - 87/100

Translates biomarker results into health scores for reproductive and thyroid health

Personalised health targets

Triiodothyronine (T3, free)

Healthy
Green target bar

6.5 (pmol/L)

Next target 4.5 - 5.5 (pmol/L)

Get incremental, achievable targets based on your unique results, ensuring progress at every step

Focus where it counts

78

100

Thyroid health

GOOD

HealthCoach's smart algorithms identify the specific areas which will make the biggest impact on your journey to better health

Guidance for optimal health

78

100

Thyroid (T3 v T4)

GOOD
Dr Thom Phillips

Although TSH is suppressed, T4 is in range. This suggests subclinical hyperthyroidism, which could indicate an intermediate situation either tending towards developing an overactive thyroid or the process of altering dose of medication to regulate a thyroid condition.

Get tailored advice which considers your gender, age, hormone treatments and menstrual cycle to help you reach optimal health

Tiredness & Fatigue Blood Test, recommended by our doctors

"Our Tiredness & Fatigue Blood Test helps uncover underlying causes of persistent exhaustion. It evaluates factors like anaemia, thyroid function, and nutrient deficiencies. Identifying the root cause enables targeted treatment, addressing fatigue and restoring energy levels, so you can enjoy a more active life."

Dr Thom Phillips

Dr Thom Phillips

Clinical lead

Frequently asked questions

This is what our customers ask us about the most. For more information, try our help centre.

What does this test check?

The Blood Test for Tiredness & Fatigue measures key biomarkers linked to tiredness and fatigue, including iron, vitamin B12, vitamin D and thyroid function. It helps identify deficiencies and imbalances that may be affecting your energy levels.

What causes tiredness & fatigue?

Fatigue can be caused by a range of factors, including nutrient deficiencies, hormone imbalances, lack of sleep, stress, and underlying health conditions like thyroid disorders or diabetes.

Can caffeine make you tired?

Yes! While caffeine gives a temporary boost, too much can lead to energy crashes and disrupt sleep, making you feel more tired in the long run.

Can diabetes make you tired?

Yes, both high and low blood sugar levels can cause fatigue by affecting energy metabolism and insulin function.

Can antibiotics cause tiredness?

Some antibiotics can cause fatigue as a side effect, particularly if they disrupt gut bacteria or cause dehydration.

Can antidepressants cause tiredness?

Yes, some antidepressants have sedative effects or impact neurotransmitters involved in energy and alertness, leading to drowsiness or fatigue.

Why am I always sleepy?

If you’re constantly sleepy, it could be due to nutrient deficiencies, poor sleep quality, stress, thyroid issues, or underlying conditions like sleep apnoea. A blood test can help uncover possible causes.

Does high blood pressure make you tired?

Yes, high blood pressure can lead to fatigue, either due to the strain on your heart or as a side effect of certain blood pressure medications.

How can I get more energy?

Boosting your energy levels starts with addressing the root cause. Ensuring you get enough sleep, balanced nutrition, regular exercise, and stress management can help. If fatigue persists, a blood test can identify deficiencies or hormonal imbalances that may be affecting your energy.

How soon will the test arrive?

Orders placed before midday Monday-Friday are dispatched the same day via Royal Mail Tracked 24, so you’ll receive your test quickly.

How secure is my data?

Your data is fully encrypted and protected, and we comply with strict data privacy regulations. Your results are confidential and only accessible through your secure account.

Can I have someone take my blood for me?

Yes, we have several options for having a trained healthcare professional collect a blood sample for you, whether at your home or our partner clinics. You can choose your collection method during checkout.

Does a doctor review my results?

Yes, all test results are reviewed by a registered doctor (unless you opt out), ensuring you receive accurate, expert-validated insights.

Can I download the results to share with my GP?

Yes, your results can be downloaded as a PDF so you can easily share them with your GP or healthcare provider.

How soon will the test arrive?

If you order your test before midday on a Monday to Friday then your kit will be dispatched the same day.

All our kits are sent out via Royal Mail Tracked24, so it should be with you within 1-2 working days.

How secure is my data?

We have strict processes in place to ensure the protection of your data. Following GDPR the company also operates under tight legal rules about the sharing of data which ensures that data is only shared if it is crucial to the delivery of our service. For example, our doctors see customer results at the time of review, however, after review, access to results is withdrawn.

Learn more about your data security.

Can I have someone take my blood for me?

Yes. We offer two options if you do not want to do our finger prick test. The first is a home appointment where a nurse comes to your home to take a blood sample. The second is to visit a Phlebotomy clinic near you that offers a blood sample service.

A blood sample will be taken from your vein and we will provide you with everything you need to give to the nurse to allow them to take the sample.

The nurse will give you the blood sample to return to us using the pre-paid envelope provided.

Does a doctor review my results?

We have a team of doctors and nurses who look at all results and will comment on any results that are outside of the normal range for your age.

Can I download the results to share with my GP?

Yes, you can download your results from your health dashboard as a PDF to share with your GP.

Learn how to export your results.

We are dedicated to supporting you on improving your health

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Blood Test for Tiredness & Fatigue