What Does Testosterone Mean?
Testosterone is the primary male sex hormone, but it matters for both sexes. Low testosterone affects energy, mood, libido, muscle mass, and bone density.
What Testosterone Measures
Total testosterone measures all testosterone in blood — both bound to proteins and free. Free testosterone (the bioactive portion) is sometimes more clinically meaningful, especially in older men or anyone with elevated SHBG. Levels naturally peak in the morning, so testing is typically done before 10 AM.
Normal Ranges
Men — normal300–1000 ng/dL
Men — low< 300 ng/dL
Women — normal15–70 ng/dL
Women — elevated> 70 ng/dL
Reference ranges may vary slightly by lab. Always use the range provided on your specific test report.
What Affects Your Testosterone Level
- Aging (gradual ~1%/year decline after 30 in men)
- Obesity (fat tissue converts testosterone to estrogen)
- Poor sleep — even one week of short sleep drops testosterone
- Chronic stress and high cortisol
- Type 2 diabetes
- Medications: opioids, glucocorticoids, finasteride
- Endocrine disorders (pituitary, testicular)