Tired all the time? Find out why
Blood tests to uncover the cause of your fatigue. Iron, thyroid, vitamins, hormones, cortisol, blood sugar. Most unexplained tiredness has a cause you can find and treat. A blood test takes 15 minutes.
Find the right test for your tiredness
Tell us what your tiredness feels like and we'll point you to the panel that checks the most likely causes, with how to prepare.
What does your tiredness feel like?
This helps you choose a test. It isn't a diagnosis. If you're unsure, WhatsApp us your symptoms and we'll help.
What causes constant tiredness?
Fatigue is a symptom, not a diagnosis. These six causes are behind most unexplained tiredness, and every one is simple to check with a blood test.
Low iron
Low iron means less oxygen reaching your cells. The most common cause in women.
Thyroid trouble
A slow thyroid slows your metabolism and saps energy, often quietly for years.
Low vitamin D
Yes, even here. Low vitamin D drags down energy, mood and immunity.
Low vitamin B12
Essential for nerves and healthy red blood cells. Low levels cause fatigue and brain fog.
Blood sugar swings
Unsteady blood sugar can cause energy crashes and afternoon slumps.
The stress response
The body's stress response affects recovery, sleep quality and daytime energy.
Sources: Turawa et al. 2021 (South African review of iron deficiency in women), Canaris et al. 2000 (Colorado thyroid disease prevalence study), Eastern Cape healthcare workers study 2024 (vitamin D).
Fatigue testing packages
Start simple with iron and thyroid. Go comprehensive if you want answers fast. All packages include a plain-language Functional Health Report, produced using Optimal DX, plus the standard lab report for your doctor.
Iron Deficiency and Anaemia Package
Most start hereComplete Thyroid Panel
RecommendedVegetarian and Vegan Panel
Nine tests for the nutrients most often low on a plant-based diet: B12, iron studies, vitamin D, zinc, magnesium and calcium, plus a full blood count, cholesterol and kidney function. Fasting required, 8 to 12 hours, water only.
Vital Health Package
Thirteen markers covering the core fatigue causes in one panel: iron stores, thyroid, vitamin D, B12, blood sugar, cholesterol, liver, kidney, inflammation and a full blood count. Checks the most common blood causes of fatigue in one visit. Fasting required, 8 to 12 hours, water only.
Max Health Package
Twenty-one markers for the most thorough fatigue investigation: cortisol, full thyroid (TSH, free T4, free T3), oestrogen and testosterone, blood sugar and fasting insulin, iron, B12, vitamin D, homocysteine, calcium, magnesium, phosphate, uric acid, cholesterol, liver, kidney and a full blood count. Morning draw, book before 10am. Fasting required, 8 to 12 hours, water only.
Mental Health and Mood Panel
Thirteen markers behind mood, focus and mental energy: cortisol, DHEA-S, free testosterone and thyroid, with fasting insulin, iron, vitamin D, B12, folate, homocysteine, magnesium, calcium and inflammation. Morning draw, book before 10am. Fasting required, 8 to 12 hours, water only.
Stress and Cortisol Panel (Essential)
Ten markers for the wired-but-tired pattern: morning cortisol and DHEA-S, the two main stress hormones, plus thyroid, blood sugar, inflammation, magnesium, vitamin D and a full blood count. Morning draw, book before 10am. Fasting required, 8 to 12 hours, water only.
Functional Health Analysis
Sixteen markers for nutrient and energy status: cortisol and DHEA-S, iron, folate, B12, vitamin D, magnesium, zinc, copper, calcium, homocysteine, blood sugar, liver (gamma GT), kidney, LDH and a full blood count. Morning draw, book before 10am. Fasting required, 8 to 12 hours, water only.
Long COVID Assessment
Not sure where to start? If you are new to testing, start with the Iron and Anaemia Package plus the Thyroid Package. Together these check the two most common blood causes of tiredness. If those come back normal, move to a comprehensive panel. Or WhatsApp us and describe your symptoms.
Fasting note: Basic panels (iron, thyroid, Long COVID): no fasting required. Panels that include glucose, insulin, cholesterol or cortisol, including the Vegetarian and Vegan Panel and the comprehensive packages: fast 8 to 12 hours, water only. Panels with cortisol (Max Health, Mental Health and Mood, Stress and Cortisol, Functional Health Analysis): book before 10am.
All packages: Payflex available (4 interest-free instalments). 10% student discount. 10% pensioner discount. All prices include VAT.
Frequently asked questions
What blood tests should I get if I am always tired?
Do I need to fast?
How long do results take?
What if my results are abnormal?
Is ferritin the same as iron?
Can I test for chronic fatigue syndrome?
Stop guessing. Start testing.
Most unexplained tiredness has a cause you can find and treat. A blood test takes 15 minutes. No doctor's referral.
Walk-in labs: Observatory (Cape Town), Hillcrest (Durban), Parktown North (Johannesburg). Mon to Fri, 08:30 to 16:00. Practice #1117394.
Epicentre Walk-In Labs does not provide medical diagnoses. For diagnoses and advice, consult your healthcare practitioner.