Advanced Thyroid Blood Tests: Beyond TSH in Private Clinics
Reviewed by Dr Lauren Holland • Marylebone Diagnostic Centre
Results within 24–42 hours. Westminster residents receive 20% off.
Thyroid symptoms are increasingly common among adults in London. Many people experience unexplained weight gain, fatigue, low mood, cold sensitivity, hair loss, dry skin or brain fog. While NHS screening often checks TSH only, this does not always provide a full picture of thyroid health. At Marylebone Diagnostic Centre, our advanced thyroid testing panel evaluates TSH, Free T4, Free T3, thyroid antibodies and related metabolic markers to give a more accurate assessment.
This blog explains why advanced thyroid testing matters, what symptoms are linked to thyroid imbalance, and which tests provide the clearest answers.
What the Thyroid Does
The thyroid controls:
- metabolism
- temperature regulation
- weight balance
- energy levels
- heart rate
- hair growth
- menstrual cycles
- digestion
- mood stability
Even small changes affect many body systems.
Symptoms of Thyroid Imbalance
People often report:
- weight gain
- fatigue
- cold hands and feet
- constipation
- dry skin
- brittle hair
- hair thinning
- depression or anxiety
- brain fog
- slow heart rate
- heavy periods
- low libido
These symptoms usually warrant a comprehensive thyroid assessment.
The Limitations of TSH-Only Testing
TSH alone cannot diagnose:
- early hypothyroidism
- central hypothyroidism
- poor T4–T3 conversion
- autoimmune thyroid disease
- subclinical thyroid disorders
Many patients have symptoms despite “normal” TSH.
What Advanced Thyroid Testing Includes at MDC
Why People Choose Private Thyroid Testing
- Faster access to detailed results
- More extensive hormone evaluation
- Ability to test T3, antibodies and minerals together
- Explanation of results by a clinician
- Early detection of subtle thyroid issues
- Personalised follow-up plan
MDC Thyroid Profiles
Advanced Thyroid Markers Explained
| Marker | What It Shows | Why It Matters |
| TSH | Thyroid stimulation | First screening marker |
| FT4 | Available hormone | Low in hypothyroidism |
| FT3 | Active hormone | Low despite normal TSH |
| TPO antibodies | Autoimmune activity | Detects Hashimoto’s early |
| Ferritin | Iron stores | Needed for hormone production |
| Vitamin D | Metabolic support | Low in most thyroid patients |
| B12 | Energy & nerves | Often low with thyroid issues |
FAQs
Book Your Advanced Thyroid Testing at MDC
Marylebone Diagnostic Centre
73 Baker Street, London W1U 6RD
Tel: +44 7495 970109
Open Monday–Saturday, 08:00–16:00
Fast, private and confidential results within 24–42 hours.
Quick Links
- Cardiac Profile
- HbA1c Test
- Full Lipid Panel
- Fatigue and Energy Profile
- Kidney Function Test
- Electrolytes Test
- Liver Function Test
- Thyroid Function Test
- Magnesium Test
- Full Blood Count
- Urinalysis & Culture
- Book an Appointment
- ECG Testing
- Wellness Profile
- Pancreatic Profile
- Women’s Health Tests
- Female Fertility Hormone Panel
- HIV 4th Generation Test
- Advanced Sexual Health Panel
- Sexual Health Tests
- Syphilis Test
- Hepatitis B & C Tests
- Urine Analysis











