What is Testosterone?
Testosterone is the primary male sex hormone, though it is present and important in females too. It supports muscle mass, bone density, libido, mood, red blood cell production, and fat distribution.
Total testosterone includes both bound and free fractions. Free testosterone (the biologically active form, not bound to proteins) can be measured separately and may better reflect symptoms, particularly when SHBG is abnormal.
Why might Testosterone be low?
Low testosterone in males (hypogonadism) can cause fatigue, reduced libido, mood changes, reduced muscle mass, and bone loss. In females, low testosterone can also affect energy and libido, though the clinical significance of borderline values is debated.
This information is educational. A single out-of-range result is rarely the whole picture — a healthcare professional can interpret your numbers alongside your overall health and history.
Context questions that matter
- →Was this result slightly or clearly outside the reference range?
- →Were related markers also high or low?
- →Is this new compared with previous tests?
- →Could recent illness, exercise, fasting, alcohol, supplements, or medication affect it?
- →Do you have symptoms that should be discussed with a clinician?
Lifestyle considerations
- •Sleep, stress management, and maintaining a healthy weight support testosterone levels
- •Testosterone naturally declines gradually with age in both sexes
Questions to ask your doctor
- →Could time of day, cycle phase, stress, sleep, medication or supplements affect this result?
- →How does this compare with related hormones such as LH, FSH, testosterone, estradiol, prolactin, cortisol or DHEA-S?
- →Is this a one-time result, or part of a pattern that needs repeat testing?
Don't guess from one flagged result.
Start with the most relevant panel and see how your markers fit together in plain English.
Frequently asked questions
What does low Testosterone mean?
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Low testosterone in males (hypogonadism) can cause fatigue, reduced libido, mood changes, reduced muscle mass, and bone loss. In females, low testosterone can also affect energy and libido, though the clinical significance of borderline values is debated.
What is Testosterone?
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Testosterone is the primary male sex hormone, though it is present and important in females too. It supports muscle mass, bone density, libido, mood, red blood cell production, and fat distribution.
Does timing matter for hormone tests?
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Often yes. Time of day, menstrual cycle phase, sleep, acute stress, medications and supplements can all affect hormone results. Morning samples and same-time-of-day repeat testing are typically preferred for hormones with a daily rhythm.
Should hormone results be compared with related hormones?
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Yes — hormones are usually interpreted as patterns. TSH is read with Free T4 and Free T3; testosterone is read with LH, FSH and SHBG; cortisol is read with ACTH and the time of day. Single values out of context can be misleading.
What supports healthy Testosterone levels?
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Sleep, stress management, and maintaining a healthy weight support testosterone levels. Testosterone naturally declines gradually with age in both sexes