The TSH:T4 Ratio measures the balance between thyroid-stimulating hormone (TSH) and thyroxine (T4) levels, key regulators of metabolism and energy production. In an optimal range, this ratio supports efficient metabolism, hormone regulation, and overall wellbeing. Monitoring it can help track energy, metabolic efficiency, and long-term health, giving you control over your lifestyle choices. By testing and tracking this biomarker, you gain valuable insights into your body's energy systems and can take proactive steps to optimise your health.
Vively's health team can help you test TSH / T4 Ratio. You start with the Baseline Health Check, then add this test.
Every marker in range? Get your $99 back. T&Cs apply.Want to save 25%? Try our 4-Month Reset insteadThe TSH:T4 ratio compares thyroid-stimulating hormone (TSH) with thyroxine (T4), both essential for regulating metabolism and energy production.
The TSH:T4 ratio plays a key role in regulating metabolic function, energy levels, and overall vitality. Tracking it can support better energy management, enhancing longevity and general wellbeing.
The lab range for the TSH:T4 ratio is 1.3 to 2.5. Vively's optimal range is 1.5 to 2.0, which sits inside the lab range. Optimal ranges are what we aim for, not diagnostic cut-offs, and they can vary by individual and testing method. For accurate interpretation, consult your healthcare professional.
Divide your TSH (in mIU/L) by your free T4 (in ng/dL). Australian labs report free T4 in pmol/L, so convert it first by multiplying by 0.0777.
For example, a TSH of 2.0 mIU/L with a free T4 of 15 pmol/L: 15 × 0.0777 = 1.17 ng/dL, and 2.0 ÷ 1.17 = 1.7. That sits inside the optimal range.
Lifestyle factors such as diet, stress, and sleep can affect thyroid function and the TSH:T4 ratio. Genetics, age, and environmental factors also play a role in regulating these hormones.
An imbalance in the TSH:T4 ratio may indicate irregular metabolic function or other aspects of wellness that could benefit from lifestyle adjustments.
Maintaining a balanced diet rich in nutrients, managing stress, and staying active can help support healthy thyroid function and keep the TSH:T4 ratio in a healthy range.
How to get it: Available as one of our specialty add-on tests. Your test referral is issued straight away when you order. See how a blood test without a referral works.
Related tests: Free Thyroxine (T4), Free Triiodothyronine (T3), Thyroid Stimulating Hormone (TSH), FT3 / FT4 Ratio
The Baseline Health Check reads 70+ markers, then your dietitian turns your results into a plan. $99 a month, first test included.
Every marker in range? Get your $99 back. T&Cs apply.