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
Or 3 interest-free payments of £ 45.67
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.
£85
3 Interest-free payments Learn more
What gets tested?
6 Biomarkers
Blood sample collection options
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.
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.
Getting the insights you need to improve your health has never been easier.
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.
You’ll receive a detailed report with your personalised scores, insights into your energy levels, including doctor-reviewed comments.
Your results highlight areas needing attention, giving you the data to seek further help and improve energy.
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
"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
Clinical lead
Our team of specialist doctors, dieticians and biomedical scientists are here to help you be in the best of health.
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.
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Blood Test for Tiredness & Fatigue