Many serious diseases develop without symptoms and only reveal themselves when treatment becomes more difficult and less effective. This is why prevention is so important, and one of the simplest and most accessible ways to check your overall health is through regular blood tests.
Once a year, it is worth pausing for a moment and carrying out a basic panel of tests that can help detect diabetes, anaemia, hormonal disorders, liver or kidney problems and many more. In this article, we explain which blood tests are worth doing prophylactically, what information they provide, and how to prepare for them.
Basic blood tests recommended once a year
Once a year, it’s worth doing a set of basic blood tests that provide a general overview of the body’s health. Below are the most important ones, with explanations of what they measure and what information they can provide.
Full Blood Count (FBC)
One of the most commonly performed diagnostic tests. It allows assessment of:
- quantity and quality of red blood cells (erythrocytes),
- haemoglobin and haematocrit levels,
- number of white blood cells (leukocytes) – important in infections, inflammation, or autoimmune diseases,
- number of platelets (thrombocytes).
Abnormalities may indicate anaemia, inflammation, infections, or bone marrow disorders.
ESR (erythrocyte sedimentation rate) or CRP (C-reactive protein)
These are inflammation markers. CRP rises more quickly and is more precise, while ESR can remain elevated long after an infection.
- Elevated CRP may indicate an infection, inflammation, or even cancer.
Fasting glucose
A basic test for diabetes and insulin resistance.
- Normal: 70-99 mg/dl
- 100-125 mg/dl may indicate prediabetes
- 126 mg/dl or higher – possible diabetes (requires further testing)
Lipid profile
Assesses lipid metabolism – key for preventing cardiovascular diseases.
- Total cholesterol
- LDL (“bad”) cholesterol
- HDL (“good”) cholesterol
- Triglycerides
Abnormal results indicate the need for dietary and lifestyle changes, and sometimes medication.
TSH (thyroid-stimulating hormone)
Regulates thyroid function. Abnormal levels may indicate:
- hypothyroidism (TSH ↑)
- hyperthyroidism (TSH ↓)
- autoimmune thyroid disorders (combined with FT3, FT4, anti-TPO tests)
ALT, AST – liver enzymes
Elevated levels may indicate:
- liver overload (e.g., medications, alcohol)
- fatty liver
- viral hepatitis
Creatinine and eGFR
Assess kidney function. eGFR (estimated glomerular filtration rate) can detect even early kidney dysfunction.
Electrolytes: sodium, potassium, calcium, magnesium
Abnormal levels may lead to heart, muscle, or nervous system dysfunction. Useful especially for people with hypertension, arrhythmias, or those taking diuretics.
Vitamin D3 (25(OH)D)
Most people in Poland (and the UK) have a deficiency, especially in autumn and winter. Low levels may cause:
- weakened immunity
- mood disorders
- bone and muscle issues
Ferritin and iron – assessment of iron status
Helpful in diagnosing anaemia. Low ferritin/iron suggests iron deficiency; high levels may indicate inflammation or chronic disease.
Additional blood tests for women and men
Besides generic tests recommended for everyone, some parameters are particularly important depending on gender.
Additional tests for women
- Prolactin (PRL). A hormone affecting menstruation, fertility, and lactation. Elevated levels can cause irregular periods, difficulty conceiving, low libido.
- Oestradiol (E2). Main female sex hormone – important for cycle disorders, menopause, or suspected oestrogen deficiency.
- FSH and LH (pituitary hormones). Assess ovarian and pituitary function. Recommended for irregular periods or suspected early menopause.
- Testosterone (total and free). Useful for symptoms such as excess hair growth, acne, low libido, or fertility problems.
- CA-125 (ovarian cancer marker). Optional test for women over 40 with a family history of ovarian cancer or concerning symptoms.
Additional tests for men
- Total (and optionally free) testosterone. Key hormone for libido, muscle mass, mood, and fertility. Low levels may be due to stress, obesity, ageing, or endocrine disorders.
- PSA (prostate-specific antigen). Cancer marker used to assess prostate cancer risk. Recommended for men over 50, or earlier if symptomatic or with family history.
- SHBG. Helpful when testosterone results are unclear.
- Prolactin (PRL). Elevated levels may lower testosterone and cause erectile problems.
These additional hormonal tests should be done depending on age, symptoms, lifestyle, and family history. They are not required every year but are a valuable addition to prevention, especially after age 30.
Why are periodic blood tests necessary?
Regular blood tests are a cornerstone of preventive healthcare. Although many people get tested only when symptoms appear, periodic blood tests detect disease at a very early stage – often before any symptoms develop.
Early detection of chronic diseases
Diabetes, heart disease, hypertension, thyroid disorders, or blood cancers can remain silent for a long time. Blood tests allow early detection, improving treatment outcomes.
Assessment of general health
Tests such as FBC, lipid profile, or glucose levels help assess general health and detect concerning trends early.
Monitoring treatment effectiveness
Patients taking medication (e.g., for thyroid, hypertension, depression) should have regular blood tests to ensure treatment is effective and safe for the liver, kidneys, and circulatory system.
Tracking lifestyle and diet changes
Blood tests help evaluate whether your diet, supplements, or physical activity are having the desired effect.
Prevention saves money and reduces stress
Treating advanced diseases is expensive and emotionally burdensome. Regular tests are an investment in long-term health.
How are blood tests performed at the Polish Clinic in the UK, and why should they be done fasting?
Preventive blood tests are performed by drawing a small (5 ml) sample from the vein in the elbow. The tube contains an anticoagulant. Most tests should be done in the morning. Why is timing so important?
Diagnostic value may be reduced if the patient:
- is overtired or stressed (avoid strenuous activity before testing),
- has eaten or consumed large amounts of fluids within 8-12 hours before the test.
Blood parameters also follow a daily rhythm – values differ between morning and evening. Therefore, many tests must be done fasting.
There are exceptions to these rules – both regarding the method of collecting blood and the strict requirement to fast before testing. These differences apply mainly to infants and young children, explains the Polish paediatrician in Coventry. In their case, a blood sample may be taken from a finger or heel. This is called a capillary blood draw.
For little ones under the age of three, feeding is allowed approximately one hour before the planned test (inform the doctor interpreting the results about this). Some tests do NOT require fasting and can be done at any time, including:
- serology for toxoplasmosis and Lyme disease
- blood type testing
- parasite testing
- IgE antibodies
- genetic tests
- allergy tests
- thyroid and sex hormone tests
- vitamin D and B12 levels
Another test not requiring fasting is the PAPP-A test, performed during pregnancy.
How to prepare for a full blood count test (FBC)?
FBC assesses both quantity and quality of blood cells: red blood cells, white blood cells, and platelets. These components are crucial for oxygen transport, immunity, and blood clotting.
Blood testing is safe. While slightly uncomfortable, the procedure is quick and not painful when performed properly.
Why is it worth having your blood tested regularly?
First of all, blood tests are highly effective. They allow you to monitor your overall health. Even a small amount of blood is an invaluable source of information about what is happening throughout your entire body. It makes it possible to detect various conditions at an early stage and, as a result, begin appropriate treatment immediately.
To ensure reliable FBC results:
- FBC should be done fasting – eating affects laboratory parameters. Avoid food for at least 8 hours, ideally 12. Eating may lead to elevated levels of glucose, cholesterol, and triglycerides. As a result, the test results will be distorted.
- You may drink a small amount of water (one glass). Proper hydration helps with sample collection but avoid drinking too much right before the test.
- Avoid alcohol, cigarettes, coffee, and even tea – Both alcohol and cigarettes, as well as coffee and even tea (due to their caffeine content), can affect various blood parameters. Falsely elevated results may also apply to the levels of certain hormones. It’s best to avoid consuming alcohol for two days before your scheduled test. You should also refrain from smoking. In cases of severe addiction, when this is not possible, inform the doctor at the Polish clinic in the UK. This is very important for correctly interpreting the results.
- Medication use should be discussed with a doctor. If possible, take medications after the test – especially supplements and vitamins.
- Menstruation is not a contraindication – although some parameters may vary slightly, results remain reliable. Although some parameters may be slightly altered (such as haemoglobin levels), when ferritin and iron levels are measured as well, the results remain reliable. Regardless of the phase of the menstrual cycle, it is therefore possible to carry out the tests. Inform the doctor if the sample was taken during menstruation.
Polish doctor in the UK recommends performing FBC annually regardless of age or physical condition. If abnormalities appear, an FBC with differential may be recommended. This is an extended form of basic FBC testing.
If you want to look after your health under the care of a professional medical team at the Polish Clinic in Coventry, we encourage you to get in touch.
Would you like to learn more about preventive blood tests? Wondering how much they cost? Check our price list and find out more.
