Testosterone & SHBG
Measures a hormone that affects energy, libido, muscle, mood and bone - in both men and women.
TypeBlood test
HowMorning blood draw (before 10am).
How oftenIf symptoms; confirm a low result with a second morning test.
BeforeTest in the morning, fasting if possible.
WhoMen with low libido, fatigue or muscle loss; women with irregular cycles, acne or excess hair.
Why one number isn’t the whole story
Much of your testosterone is bound to a protein called SHBG and isn’t available to your tissues. Total testosterone alone can mislead.
Total testosterone
“How much is there?”
All testosterone in the blood. Best measured in the morning.
First test
SHBG
“How much is locked up?”
High SHBG means less free hormone, even with a normal total.
Context
Free testosterone
“How much can my body use?”
Calculated from total and SHBG - often more meaningful.
Most useful
Is it right for you?
Worth considering if…
- Men: low libido, erectile problems, fatigue, low mood or muscle loss.
- Women: irregular periods, acne, excess hair (possible PCOS).
- You’re considering hormone therapy.
A better option if…
- You feel fine - routine testing isn’t recommended.
- A single low result - repeat in the morning before drawing conclusions.
How it’s measured
Total testosterone
Morning blood draw.
SHBG + calculated free testosterone
Adds context.
LH / FSH
Shows whether low testosterone comes from the testes or the brain.
The full picture
What is it?
A blood test for testosterone and its binding protein, SHBG.
What type of test is it?
A blood biomarker panel.
What does it measure?
Total testosterone, SHBG and calculated free testosterone.
Why might someone consider it?
To investigate symptoms of low or high testosterone.
Who is it most relevant for?
Men and women with relevant symptoms.
How is it performed?
A morning blood draw.
How often might it be considered?
If symptoms; confirm with a repeat.
What can the result help you understand?
Whether hormone levels could explain symptoms.
What are its limitations?
Levels vary by time of day, sleep and illness.
What should it be viewed with?
LH, FSH, prolactin, thyroid, sleep and weight.
Where to get it
Through your provider
The simplest route - often covered when there’s a clear reason.
Lab services
e.g. Quest Diagnostics, Labcorp.
Direct-to-consumer panels
e.g. Function Health, InsideTracker.
Names are examples only, not endorsements. Your provider can often order the same test - and help interpret it.
Connected to
Questions to ask your provider
- Should I retest in the morning?
- What’s causing a low result?
Ziva Health
One test is a snapshot. Ziva shows the whole story.
Ziva brings your lab results, wearables and daily readings together - and Isabella tells you what’s changing and what to ask your provider next.
Refer Ziva to my provider / care team
Is your provider not on Ziva yet? Send them a link in under a minute - once they join, they’ll see your Testosterone & SHBG result alongside your other trends and get alerts directly.
Refer my providerAlready seeing your provider?
Bring your Ziva 30-day report to your next appointment - your Testosterone & SHBG result and daily trends in one view, so the conversation starts with the full picture.
Get my 30-day reportNo provider? Find a clinical partner
Being listed doesn’t mean everyone needs this test. Educational only — not medical advice. Results should be interpreted with a qualified clinician. ← Back to Know What to Test