Educational information only. At Precursor, hormone testing is requested and reviewed by a clinician and considered alongside your history and other markers, not as a stand-alone diagnosis. Testing is performed in NATA-accredited laboratories to ISO 15189 standards.

What is SHBG?

SHBG, or sex hormone-binding globulin, is a protein made by the liver that binds tightly to sex hormones, especially testosterone and oestradiol, and carries them in the blood. Hormone bound to SHBG is held in reserve rather than active, so SHBG effectively controls how much of your sex hormones are available.

Why it matters

SHBG is the key to interpreting testosterone correctly. A high or low SHBG can make a total testosterone misleading, so measuring it allows a clinician to calculate free testosterone and understand your true hormonal status. It is also influenced by metabolic health, thyroid and other factors.

What your results can mean

Lower than expected

A low SHBG is often linked to insulin resistance and metabolic strain, and can leave more free hormone available. It is interpreted alongside testosterone and your metabolic markers.

Higher than expected

A high SHBG can accompany thyroid, liver or other factors, and can lower the amount of free hormone. It is read within the overall hormonal picture.

Reference ranges in Australia

SHBG is reported in nanomoles per litre (nmol/L), with ranges that differ by sex and age. Read your result against your own report and alongside your testosterone.

Understanding your hormones with Precursor

SHBG is most useful read with testosterone and your metabolic markers. At Precursor, hormone testing is requested and reviewed by a clinician, so your result is read in context. If this is something you would like to understand, you can speak with Precursor's clinical team about whether testing is right for you.