Tired All the Time? Tests to Rule Out Underlying Illness
Constantly tired? Discover key blood tests for fatigue—thyroid, B12, Vitamin D, anaemia, and more. Book tiredness test packages online at Apollo 24|7.
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Last updated on 1st Aug, 2025
Tired All the Time? Tests to Rule Out Underlying Illness
In today’s fast-paced world, it’s not unusual to feel exhausted at the end of a long workday. But what if that constant feeling of tiredness doesn’t go away, even after a full night’s sleep, a weekend of rest, or even a holiday break? For many working adults, persistent fatigue can be more than just a symptom of a busy lifestyle. If you're feeling tired and can't understand why, perhaps it's time you looked just a little harder and had a complete medical work-up. Certain health problems, ranging from vitamin deficiencies and thyroid disorders to other ailments can drain you of energy and you're not even aware of it. Thankfully, a targeted fatigue blood test or a tiredness test package can help identify the root cause and get you back on track. In this guide, we’ll explore the most common medical causes of chronic fatigue, key blood tests that can help uncover hidden issues, how to choose the right tiredness test package and what to do after getting your results.
Common Medical Reasons for Tiredness
Fatigue isn’t just about feeling sleepy. It’s a lingering sense of physical or mental exhaustion that doesn’t improve with rest. If you've ruled out lifestyle causes like poor sleep habits, high stress, or overwork, it’s worth checking for medical conditions that are often overlooked. These include:
1. Thyroid Disorders
Your thyroid gland regulates metabolism. When it's underactive (hypothyroidism), everything slows down, including your energy levels. Symptoms like dry skin, weight gain, and sluggishness often accompany the fatigue.
2. Vitamin B12 Deficiency
B12 plays a crucial role in energy production, red blood cell formation, and brain function. A deficiency can cause extreme tiredness, brain fog, and even numbness or tingling in the hands and feet.
3. Low Vitamin D
Vitamin D deficiency is alarmingly common, particularly among people who spend most of their time indoors, like many office workers. Low levels are linked to fatigue, bone pain, and mood disturbances.
4. Anaemia (Low Haemoglobin)
Haemoglobin carries oxygen throughout your body. If your levels are low, you’ll feel tired even after minor physical activity. Anaemia is often due to iron deficiency, blood loss, or chronic illness.
5. Diabetes or Blood Sugar Issues
Unregulated blood sugar, either too high or too low, can leave you feeling drained and foggy. Diabetes-related fatigue can be one of the first symptoms people notice before diagnosis.
6. Liver or Kidney Dysfunction
Your liver and kidneys filter toxins and manage vital chemical balances. If these organs aren’t functioning well, toxins can accumulate in your system, leading to overwhelming fatigue.
The Role of a Fatigue Blood Test in Diagnosis
When it comes to identifying why you're feeling constantly tired, blood tests can provide valuable answers. A fatigue blood test or tiredness test package typically checks for multiple health indicators in one go, allowing your doctor to pinpoint any imbalances or deficiencies that may be contributing to your symptoms. At Apollo 24|7, you can explore top-booked blood test packages tailored to uncover the root causes of fatigue. Some of these can be booked online and even include home sample collection, making it easy for busy working adults to get tested.
Key Tests to Include in a Tiredness Test Package
If you're constantly tired, your doctor may recommend one or more of the following tests to check for common underlying causes:
1. Thyroid Profile Tests (T3, T4, TSH)
These tests measure your thyroid hormones. An underactive thyroid (hypothyroidism) slows your metabolism and leads to fatigue, sluggishness, and cold intolerance.
Who should take it: Anyone with unexplained fatigue, weight gain, dry skin, or mood changes.
2. Vitamin B12 Test
This test checks for B12 levels in the blood. B12 is essential for nerve function and energy metabolism. A deficiency can result in tiredness, weakness, and memory issues.
Who should take it: Vegetarians, vegans, older adults, and those with gastrointestinal issues like IBS or ulcers.
3. Vitamin D Test
Vitamin D deficiency can leave you feeling persistently low on energy and may also impact your immune system and bone health.
Who should take it: Those who avoid sun exposure, wear full-body covering clothes, or work in indoor environments.
4. Complete Blood Count (CBC)
This checks haemoglobin and red blood cell counts to detect anaemia. It also helps identify infections or other blood-related issues.
Who should take it: Anyone with weakness, shortness of breath, or pale skin.
5. Blood Sugar Tests (Fasting, PP, and HbA1c)
These tests measure how your body handles sugar. Abnormal levels can indicate prediabetes or diabetes, both of which can cause chronic tiredness.
Who should take it: Anyone with a family history of diabetes, weight gain, increased thirst, or frequent urination.
6. Liver Function Test (LFT)
This panel measures enzymes and proteins that reflect liver health. A compromised liver can lead to persistent exhaustion.
Who should take it: Those who drink alcohol regularly or have a history of jaundice, hepatitis, or unexplained weight loss.
7. Kidney Function Test (KFT)
Your kidneys remove waste from the blood. Poor kidney function leads to toxin buildup, causing fatigue and swelling.
Who should take it?
- Anyone with high blood pressure, diabetes, or a family history of kidney problems.
8. Ferritin, Folate, and Magnesium Tests
These can be added for a deeper look into micronutrient deficiencies linked with fatigue. There are comprehensive Vitamin Check packages in Apollo 24|7 which are economically best.
Book a Comprehensive Vitamin Check Package
Signs You Need a Fatigue Blood Test
If you answer ‘yes’ to several of the following questions, consider booking a tiredness test package:
- Do you wake up tired even after 7 to 8 hours of sleep?
- Do you experience energy crashes in the middle of the day?
- Have you recently gained or lost weight without explanation?
- Are you frequently irritable, anxious, or low in mood?
- Do you struggle with memory or concentration?
- Have you noticed hair loss, dry skin, or brittle nails?
- Are you catching colds more often than usual?
If these symptoms sound familiar, don’t ignore them. Your body could be asking for help.
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Choosing the Right Tiredness Test Package
With several options available, here’s how to choose the right test package:
1. Based on Symptoms: If your symptoms match thyroid problems, start with a thyroid profile. If you suspect anaemia or nutrient deficiency, go for a CBC + Vitamin B12 + Vitamin D combo.
2. Based on Medical History: If you have a family history of thyroid issues, diabetes, or fatigue-related illnesses, a comprehensive tiredness panel may be more useful.
3. Based on Budget and Convenience: Apollo 24|7 offers affordable packages with online booking and home sample collection.
What Happens During the Test?
Most fatigue blood tests are straightforward and minimally invasive. Here's what you can expect:
- No Special Preparation: Some tests require fasting (like blood sugar and lipid profile), while others don’t. Your provider will inform you in advance.
- Sample Collection: A trained technician draws a small amount of blood from a vein in your arm.
- Quick Process: The entire procedure usually takes less than 10 minutes.
- Reports: Results are typically available within 24 to 48 hours.
If you opt for home sample collection, you can get tested without even leaving your house, ideal for busy professionals or those too tired to travel.
Understanding Your Results
Your doctor will help you interpret the results, but here’s a rough idea:
After the Test: What To Do Next?
Getting a diagnosis is the first step. The next involves action.
- Treat the Root Cause: If you're deficient in B12 or D, your doctor may suggest supplements or injections. If your thyroid is underactive, medication may be prescribed.
- Improve Lifestyle Habits: Balanced diet, regular exercise, hydration, and sleep hygiene are essential.
- Follow-up Testing: If abnormal, some tests may need to be repeated in 3–6 months.
- Ongoing Monitoring: If diagnosed with a chronic condition like diabetes or thyroid disorder, you may need periodic testing to track progress.
Conclusion
Feeling tired all the time doesn’t have to be your default state. With the right tests and follow-up care, you can uncover hidden health issues, take charge of your well-being, and get back to living with energy and focus. Whether it's correcting a vitamin deficiency, treating a thyroid imbalance, or simply giving your body the support it needs, early diagnosis makes all the difference. So, if you’ve been running on empty despite your best efforts, don’t brush it off as just stress or age. Book a fatigue blood test or tiredness test package today and take the first step toward renewed vitality. Book Tiredness Tests Now at Apollo 24|7. Your energy is your most valuable asset, protect it with knowledge, action, and the right health support.
