Men's Health
Testosterone
The primary male sex hormone.
Overview
Testosterone is the main androgen in males and is important for libido, mood, muscle mass, body hair, fertility, and red blood cell production. Levels vary naturally over time and with age, but low levels can cause symptoms that are worth investigating.
What to know
Low testosterone is not a diagnosis based on a single blood result alone. Doctors usually look at symptoms, repeat measurements, and whether there is an underlying cause such as obesity, sleep problems, stress, steroid use, pituitary disease, or testicular issues.
Common blood tests
A morning total testosterone is the usual first test, sometimes repeated if the result is borderline. Free testosterone, SHBG, LH, FSH, prolactin, and thyroid tests may be added depending on the pattern.
Signs to watch for
Low libido, fatigue, decreased morning erections, reduced muscle mass, low mood, brain fog, and increased body fat can all be linked to low testosterone. Not all of these symptoms are caused by testosterone alone.
Lifestyle information
Sleep, exercise, healthy weight, and reducing excess alcohol can all support better hormonal health. If testosterone is low because of an underlying condition, treating that cause is often more important than simply adding supplementation.
When to seek medical advice
See a doctor if you have persistent symptoms of low testosterone or if you are considering treatment. Testosterone therapy should be guided by a clinician because it can affect fertility, blood counts, and cardiovascular risk.