Have you ever considered getting a blood test? If so, you may have wondered how vital blood testing truly is. The truth is, blood tests are one of the most essential diagnostic tools in modern medicine. They are used not only to assess your general health but also to detect and monitor a wide range of conditions, from infections to hormonal imbalances and chronic diseases.
Routine blood tests are typically carried out by your GP and include analysis of red blood cells, white blood cells, platelets, and haemoglobin. However, under certain circumstances, more detailed blood panels are needed to detect substances not measured by routine tests. These advanced screenings help identify problems that are otherwise invisible through general check-ups, such as nutritional deficiencies, liver function, hormonal changes, or specific disease markers. Whether you're managing symptoms or simply checking in on your health, explore options at Home Blood Tests, which offers a variety of convenient and discreet testing kits delivered to your door.
Whether you're experiencing symptoms, managing a known condition, or simply taking charge of your health, regular blood testing provides a clear snapshot of what’s happening inside your body.
Red blood cells (RBCs) are fundamental to your health, as they are responsible for transporting oxygen from the lungs to every cell in the body. They also return carbon dioxide to the lungs so it can be exhaled. When your red blood cell count is too low—a condition known as anaemia—you may experience fatigue, weakness, dizziness, or shortness of breath, as your body struggles to get the oxygen it needs.
In men, a healthy red blood cell count is generally considered to be 4.7 to 6.1 million cells per microlitre, while in women it ranges from 4.2 to 5.4 million. If your test result falls below these figures, further investigation is usually required. Low RBC levels can be due to nutritional deficiencies (such as iron or vitamin B12), blood loss, bone marrow disorders, or chronic diseases.
Regular testing can help identify and treat these conditions early. Simple changes like improving your diet, taking supplements, or managing an underlying illness can restore healthy red blood cell levels and boost overall vitality. For a clearer picture of your red blood cell health and related markers, the Full Blood Count Test provides an in-depth analysis of red and white blood cells, haemoglobin, and platelets, making it an essential tool for anyone experiencing unexplained tiredness or symptoms of low oxygen levels
White blood cells (WBCs) are the immune system’s soldiers. They identify, target, and destroy pathogens like bacteria, viruses, and other foreign invaders. Beyond fighting infections, WBCs also play a role in inflammation, allergic responses, and immune memory—allowing your body to respond more quickly to familiar threats.
A normal white blood cell count ranges from 4,500 to 11,000 cells per microlitre. A count lower than this may indicate an increased risk of infection, while a higher count could suggest inflammation, an active infection, or in rare cases, leukaemia or autoimmune conditions.
Monitoring your white blood cell count is essential, especially if you’re prone to infections or are on medications that affect immunity. Changes in your WBC levels can also provide early warning signs of illness before symptoms appear, allowing for faster diagnosis and treatment.
For those with chronic fatigue or inflammation, the CRP Blood Test measures C-reactive protein, a key marker of inflammation, and is useful in identifying hidden infections or inflammatory diseases before more serious symptoms appear.
Platelets, also known as thrombocytes, are small, colourless cell fragments that play a crucial role in blood clotting. When an injury occurs, platelets are the first responders—they rush to the site, clump together, and form a clot to stop bleeding. Without them, even minor injuries could result in excessive blood loss.
A healthy platelet count falls between 150,000 and 450,000 platelets per microlitre of blood. Low platelet levels (thrombocytopenia) can lead to symptoms like prolonged bleeding, easy bruising, or frequent nosebleeds. Causes may include autoimmune disorders, infections, liver disease, or side effects from medication.
On the other hand, high platelet levels (thrombocytosis) may increase the risk of blood clots, which can cause complications such as stroke or heart attack. Therefore, regular blood testing helps maintain a balance, ensuring your body’s ability to heal and protect itself is functioning optimally.
If you’ve noticed slow wound healing or unusual bruising, a platelet test could reveal an underlying issue.
Haemoglobin is the protein within red blood cells that binds to oxygen and carbon dioxide, enabling these gases to be transported through the bloodstream. In essence, haemoglobin is what allows red blood cells to fulfil their role as oxygen carriers. It is also what gives blood its red colour.
In adults, normal haemoglobin levels range from 13.8 to 17.2 grams per decilitre for men and 12.1 to 15.1 for women. Low levels indicate anaemia, which can leave you feeling weak and short of breath. Common causes include iron deficiency, chronic diseases, or internal bleeding. Conversely, high haemoglobin levels might suggest dehydration, lung disease, or living at high altitudes.
Testing haemoglobin levels is part of most routine blood panels. It offers immediate insight into how well your body is oxygenating tissues and whether further tests are needed. For athletes, it can even be used to assess performance readiness and endurance capacity.
The Basic Metabolic Panel (BMP) is a group of eight tests that measure different substances in the blood. These results give doctors important information about your body’s metabolism, kidney function, electrolyte balance, and blood sugar levels.
Glucose – Elevated levels may indicate prediabetes or diabetes
Calcium – Essential for nerve transmission, muscle function, and bone health
Sodium, Potassium, Chloride, CO2 (Bicarbonate) – Help maintain fluid balance and pH levels
Blood Urea Nitrogen (BUN) and Creatinine – Waste products that reflect kidney function
Abnormal levels in a BMP can signal problems such as dehydration, kidney disease, respiratory disorders, or endocrine conditions. This panel is often requested for individuals with chronic illnesses, those experiencing symptoms like fatigue or confusion, or before surgeries.
Monitoring your metabolic health regularly allows for early intervention and tailored treatment plans, helping to avoid complications and preserve long-term well-being.
Thyroid function tests are essential for evaluating how well your thyroid gland is working. This butterfly-shaped gland, located in your neck, produces hormones that control metabolism, heart rate, temperature regulation, and energy levels. When your thyroid is underactive (hypothyroidism) or overactive (hyperthyroidism), it can lead to a variety of symptoms that often go unnoticed or are mistaken for other conditions. The Advanced Thyroid Function Blood Test checks key hormone levels like TSH, Free T3, and T4, helping diagnose conditions such as hypothyroidism or hyperthyroidism. Early detection can lead to more effective treatment and improved quality of life.
The standard thyroid panel typically includes:
TSH (Thyroid Stimulating Hormone)
Free T3 and Free T4
Thyroid antibodies (when autoimmune disease is suspected)
An imbalance in these hormones can lead to fatigue, weight changes, depression, anxiety, dry skin, hair thinning, and more. Early detection through a simple blood test can help manage these conditions with medication, diet, and lifestyle adjustments.
People with a family history of thyroid disorders, autoimmune diseases, or persistent symptoms should consider testing. It's also recommended for women during pregnancy or menopause, as hormonal fluctuations can impact thyroid health.
Liver function tests (LFTs) are a series of blood tests that measure enzymes and proteins associated with liver health. The liver performs over 500 functions, including detoxification, digestion, and nutrient storage, making its well-being vital to your overall health.
The typical liver panel includes:
ALT and AST – Enzymes that rise with liver inflammation or damage
ALP and GGT – Indicators of bile duct or gallbladder issues
Bilirubin – A waste product from red blood cell breakdown
Albumin – A protein produced by the liver
Abnormal liver function test results can indicate liver disease, fatty liver, hepatitis, or excessive alcohol intake. Symptoms like jaundice, fatigue, dark urine, and abdominal pain often lead to further investigation.
Routine LFTs are especially important for individuals taking long-term medications, consuming alcohol regularly, or dealing with chronic conditions like diabetes or obesity. The earlier liver issues are identified, the better the chance of reversing them through lifestyle changes and targeted treatments.Hormones regulate virtually every process in the human body, from metabolism and reproduction to mood and sleep. Hormonal imbalances can affect both men and women differently, but symptoms often overlap: fatigue, weight changes, mood swings, and reduced libido are common red flags. The AMH Blood Test is ideal for those planning a family, experiencing menstrual irregularities, or undergoing fertility treatment. It gives insight into ovarian health and reproductive lifespan, allowing for better planning and intervention.
Common hormonal tests include:
Testosterone and DHEA for men
Oestrogen, Progesterone, and AMH for women
Cortisol for stress response
FSH and LH for fertility and menstrual regulation
For men, low testosterone may lead to muscle loss, low energy, and erectile dysfunction. In women, hormonal changes can affect fertility, menstrual cycles, and even bone density. Hormonal blood tests provide a clear picture of where imbalances lie and guide interventions ranging from medication to dietary adjustments.
These tests are particularly valuable during puberty, pregnancy, perimenopause, and menopause—periods where hormonal shifts are most prominent. Regular testing helps maintain hormonal harmony and prevent complications.
Micronutrient deficiencies are surprisingly common and can lead to long-term health issues if undetected. A vitamin and mineral panel measures levels of essential nutrients such as:
Vitamin D
Vitamin B12
Folate
Iron
Magnesium
Zinc
Deficiencies in these nutrients can cause fatigue, poor concentration, mood disturbances, immune dysfunction, and more. Vitamin D deficiency, in particular, is widespread in colder climates and linked to weakened bones, depression, and chronic pain.
By testing your levels, you can address imbalances with supplements or dietary changes. These panels are especially important for individuals with restricted diets, chronic illnesses, or those experiencing unexplained symptoms. To support overall lifestyle improvements and monitor broader health indicators, consider exploring Welzo’s All Health Tests Collection.
Glucose. Our bodies need glucose for energy. But too much glucose could lead to diabetes.
Calcium. A mineral which is vital for nerves, muscles, and the heart.
The body uses electrically charged minerals to control acid balance and fluid levels.
- Sodium
- Potassium.
- Carbon Dioxide.
- Chloride.
Blood Urea Nitrogen. A waste product that the kidneys remove from the blood.
Not all forms of cancer can be diagnosed by a blood test. However, certain forms of cancer release antigens (chemicals that cause your white blood cells to produce antibodies to kill them).
DHEA is one of the lesser-known hormones. DHEA Sulphate plays an important role in male and female puberty.
DHEA is short for Dehydroepiandrosterone. Our body converts DHEA into testosterone and oestrogen. Although obviously, it should mainly turn into testosterone in males and oestrogen in females. If the blood test shows low levels of DHEA sulphate, a doctor may prescribe someone with additional hormones. To view our DHEA Sulphate Blood Test, click here.
At Welzo, we provide affordable, discreet, and personal blood tests.
If you want a blood test but don't want the considerable costs of health insurance, or the long waiting lists of the NHS, Welzo offers a variety of blood tests ranging from thyroid function test to routine blood test. For example, some of our blood tests can diagnose you with allergies. By knowing what you're allergic to, you'll know to avoid it. We also offer a bilirubin test. That's a chemical created from the breakdown of red blood cells, but too much can be dangerous. Tests from Welzo can also help diagnose diseases such as hepatitis, diabetes, and HIV.
As we can see, blood tests are a vital part of taking care of your health. Whether you're just doing common blood tests, checking for white blood cell levels, having a complex test to check blood sugar levels, or doing other tests to find blood clotting, liver conditions, or other problems with organs. Regular blood testing is essential.
Your overall physical well-being depends on having blood test results in a range that your doctor is okay with. Most blood tests are quick, and painless, so there is no reason not to have them done. If you’re focused on performance, recovery, or fitness-related goals, the Sports Performance Tests Collection offers a range of panels tailored for athletes and active individuals.
When taking blood samples, you will usually have a small needle attached to a vein or other blood vessel. Your doctor will then collect blood, and send it off for lab tests. During these tests, your blood sample will undergo chemical processes. A routine blood test measures the types of cells that should be in your blood.
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