Blood Tests for Tiredness & Low Energy

Get to the bottom of low energy or constant feelings of tiredness with our at-home and at-clinic blood tests.

Our blood tests focus on key fatigue-related nutrients and hormones, including iron, Vitamin D, and Vitamin B12. Deficiencies in these nutrients are common causes of persistent tiredness and can be easily checked with a quick blood test. We also offer tests for thyroid function, as imbalances in thyroid hormones (like TSH, T3, and T4) are known to contribute to low energy. You can also screen for adrenal hormones such as cortisol, which plays an important role in managing stress and sustaining energy throughout the day.

Each test comes with clear instructions and access to easy-to-understand results, helping you get one step closer to understanding and managing your energy levels. Choose the test that best suits your needs and start your journey to feeling revitalised and informed about your health.

Tiredness & Fatigue Blood Test

Tiredness & Fatigue Blood Test

Results in 2 working days

Tired all the time, exhausted, or fatigued? Our test checks thyroid function, along with key vitamins that contribute to energy production.

6 Biomarkers

£85

View Test
Klarna

Or 3 interest-free payments of £ 28.33

Advanced Energy Blood Test

Advanced Energy Blood Test

Results in 2 working days

Our Advanced Energy Blood Test checks a more comprehensive range of biomarkers to help indentify or rule out causes of low energy.

23 Biomarkers

£137

View Test
Klarna

Or 3 interest-free payments of £ 45.67

Most Popular

Baseline Blood Test

Baseline Blood Test

Results in 2 working days

A general health blood test that checks bone health, heart, liver and energy levels, and nutrition.

25 Biomarkers

£115

Per test

View Test

Flexible subscription - Cancel anytime

Nutricheck – Vitamin Deficiency Test

Nutricheck – Vitamin Deficiency Test

Results in 2 working days

Looking to improve your diet and get a better understanding of your overall health and nutrition? Nutricheck home blood test can help.

14 Biomarkers

£109

View Test
Klarna

Or 3 interest-free payments of £ 36.33

Ferritin Blood test

Ferritin Blood test

Results in 2 working days

If you're feeling tired all the time and low on energy you could be suffering from low iron levels. Check with our ferritin blood test.

1 Biomarker

£41

View Test

Vitamin B12 Blood Test

Vitamin B12 Blood Test

Results in 2 working days

Check if your low energy and fatigue could be due to a lack of vitamin B12 with our Active B12 home blood test.

1 Biomarker

£50

View Test
Klarna

Or 3 interest-free payments of £ 16.67

Optimal Health

Ultimate Health Check

Ultimate Health Check

Results in 15 working days

Our most comprehensive blood test. This test gives you unparalleled insights into your health.

47 Biomarkers

£399

View Test
Klarna

Or 3 interest-free payments of £ 133

Single day test

Female Hormone Test

Female Hormone Test

Results in 2 working days

This single-day test gives a simple snapshot of your key female hormones along with thyroid function.

11 Biomarkers

£89

View Test
Klarna

Or 3 interest-free payments of £ 29.67

Male Hormone Blood Test

Male Hormone Blood Test

Results in 2 working days

Our male hormones test checks key health markers that could be causing low energy, mood changes and loss of sex drive.

12 Biomarkers

£89

View Test
Klarna

Or 3 interest-free payments of £ 29.67

Anaemia Blood Test

Anaemia Blood Test

Results in 2 working days

Our anaemia home blood test will help identify if symptoms of low energy and fatigue could be due to deficiencies in iron, vitamin B12 or vitamin D.

9 Biomarkers

£99

View Test
Klarna

Or 3 interest-free payments of £ 33

Vitamin D Blood Test

Vitamin D Blood Test

Results in 2 working days

Do you often feel tired or rundown? These could be signs of a vitamin D deficiency. Check your vitamin D levels with our home blood test.

1 Biomarker

£50

View Test
Klarna

Or 3 interest-free payments of £ 16.67

Advanced Thyroid Blood Test

Advanced Thyroid Blood Test

Results in 2 working days

Test thyroid function and check for thyroid autoimmune conditions with our advanced thyroid blood test.

5 Biomarkers

£69

View Test
Klarna

Or 3 interest-free payments of £ 23

Vial-Info

How can blood testing help?

Knowing why you’re feeling tired can help you create a plan to get back to normality. Whether it’s changing your diet, exercising more (or less, in some cases) or addressing hormone imbalances, blood tests give you the answers. Forth blood tests can be done at home or at a clinic, making them a convenient option for taking control of your health. All our tests are analysed at NHS labs and results are viewable in our app.

Question

What causes low energy?

Low energy can result from a variety of physical, mental, and lifestyle factors. Common causes include nutrient deficiencies, like low levels of iron, Vitamin B12, or Vitamin D. Hormonal imbalances, especially in thyroid and adrenal hormones, can also lead to fatigue by disrupting metabolism and stress response. Other medical conditions, such as anaemia, diabetes, and chronic fatigue syndrome, as well as poor sleep, high stress, and an inactive lifestyle, can further drain energy levels.

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Why is it important to address fatigue?

Persistent low energy can affect physical and mental well-being, leading to difficulties with focus, mood swings, and decreased productivity. Long-term fatigue may increase the risk of mental health issues, such as depression and anxiety, and can even worsen chronic health conditions. By tackling the causes of fatigue, you can improve your daily energy, maintain better mental and physical health, and prevent further health complications. Addressing fatigue can lead to lasting improvements in quality of life.

What's included in our tests?

Kit

Blood sample kit

Results within 2 working days

Tracked 24 delivery & return

Secure health dashboard

NHS lab analysis

Doctor reviewed results

Certified for quality & security

ISO Icons MDR CE

How it works

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

A Hand holding a lancet that is held up to a finger on the other hand

1. Collect your blood sample

It takes 5 minutes to collect a small sample of blood from your finger tip. Post it back to our labs using the Tracked-24 envelope included in your kit.

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2. View your results

You will receive your Results within 2 working days in the Forth app, along with the optional doctors comment and detailed report.

Metabolic health scores

3. Make improvements

The detailed report makes it easy to identify areas that need improving, make changes and track your progress.

Frequently asked questions

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

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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