The thyroid regulates your metabolism, energy, and body temperature. With TSH and Free T4, you get a clear overview of thyroid function, with personal explanation from our doctors.
Interpreted by BIG-registered doctors
Achtergrond
The thyroid is a butterfly-shaped gland in the neck that produces hormones (primarily T4 and to a lesser extent T3) which regulate the metabolism of virtually all cells in the body. In doing so, the thyroid influences your energy, body temperature, weight, heart rate, and mood.
The production of thyroid hormone is regulated by TSH (Thyroid Stimulating Hormone) from the pituitary gland. With a sluggish thyroid, TSH rises; with an overactive thyroid, TSH falls. The combination of TSH and Free T4 (the active hormone form) provides the most complete first-line picture of thyroid function.
In het kort
TSH + Free T4
Combination gives complete picture
Metabolism
Regulates energy and temperature
Pituitary control
TSH originates in the brain
NHG-compliant
Standard first-line investigation
Veelvoorkomende redenen om te meten
Hieronder enkele situaties waarin een meting van Thyroid inzicht kan bieden.
A measurement of TSH and Free T4 gives a snapshot of your thyroid function.
Unexplained changes in energy, weight, or sensitivity to temperature are sometimes associated with the thyroid.
Thyroid conditions run in families, if there is a family history, periodic testing can provide insight.
Thyroid function plays a role in fertility and pregnancy. A test may form part of preconception checks.
Those taking thyroid medication can use a test to check whether their levels remain stable.
TSH is one of the most commonly measured markers in self-requested blood tests, as a basic check.
Wat betekent uw uitslag
TSH is measured in mU/L and Free T4 in pmol/L. The combination provides a good first-line picture. Our doctor assesses your values against the reference ranges of the laboratory.
A reduced TSH generally indicates increased thyroid activity, often in combination with an elevated Free T4. Our doctor provides explanation and context for your result, so you can discuss it with your GP if you wish.
TSH and Free T4 within the reference range gives a reassuring picture of thyroid function. For specific questions, additional testing (such as TPO antibodies or Free T3) may be worthwhile.
An elevated TSH is often seen with an underactive thyroid, sometimes in combination with a reduced Free T4. For borderline elevations (subclinical hypothyroidism), repeat testing after 6–12 weeks is a common approach. Our doctor provides explanation for your result.
Hoe wij uw uitslag interpreteren
Our doctors interpret your TSH and Free T4 together, in accordance with the NHG guidelines. You receive a report in plain language, as a starting point for your own insight or a conversation with your healthcare provider.
Related tests
A single marker gives one perspective. For a broader picture you can combine Thyroid with a theme package or related markers.
Veelgestelde vragen
No, you do not need to fast for TSH and Free T4.
TSH is the hormone from the pituitary gland that stimulates the thyroid. Free T4 is the thyroid hormone itself, in the active, unbound form. The combination provides the most complete picture.
Free T3 is sometimes added for specific questions or borderline cases. TPO antibodies are measured when an autoimmune thyroid condition such as Hashimoto's or Graves' disease is suspected.
A sleeve that can easily be rolled up is practical. No other special preparation is required.
Yes, certain medications (including thyroid medication itself, biotin supplements, lithium, and some contraceptives) can influence the measurement. Please let us know so we can take this into account during interpretation.
When thyroid medication is adjusted, TSH is typically not re-measured until 6–8 weeks later, retesting sooner is of little value because the system needs time to stabilise.
You will receive a PDF report with your values and explanation. What you do with it, such as discussing it with your GP or taking no action, remains entirely your choice.
Yes, the report is written in medical language and contains all relevant laboratory information.
In the Health Guide
For €79 you receive TSH and Free T4 including personal explanation from a doctor, typically within 2 business days. No referral required.
Order Thyroid for €79 →Want to test multiple markers at once?
Combine Thyroid with other markers via Bloodworks Select. Blood draw costs are waived from €225.
Customer service
Available on weekdays from 9:00 – 17:00
