Interpretation of Testosterone Levels in a 45-Year-Old Male
Your Testosterone Levels Are Normal
Your total testosterone of 605 ng/dL and free testosterone of 90.1 pg/mL are both solidly within the normal range for a 45-year-old man, and testosterone replacement therapy is not indicated. 1, 2
Understanding Your Results
Total Testosterone: 605 ng/dL
- This is in the mid-normal range, which is exactly where clinicians target when treating hypogonadism (450-600 ng/dL) 1, 2
- The American Urological Association defines testosterone deficiency as levels below 300 ng/dL 1, 3
- Your level is double the diagnostic threshold for low testosterone 1
- For men aged 40-44 years, the normal middle tertile range is 350-473 ng/dL, and your level exceeds this 4
Free Testosterone: 90.1 pg/mL
- This is also normal for your age group 5
- Reference intervals for free testosterone in healthy men show the 2.5th to 97.5th percentile range is 66-309 pg/mL 5
- Your level falls comfortably within this range, indicating adequate bioavailable testosterone 5
- Free testosterone represents the biologically active fraction not bound to sex hormone-binding globulin (SHBG) or albumin 1, 6
Clinical Implications
What These Levels Mean
- You do not have hypogonadism (testosterone deficiency) 1, 2
- Testosterone replacement therapy is explicitly not recommended for men with normal testosterone levels, even if they have symptoms like fatigue, low energy, or desire for improved athletic performance 1
- The European Association of Urology strongly recommends against testosterone therapy in eugonadal men (those with normal levels), even for weight loss, cardiometabolic improvement, cognition, vitality, or physical strength 1
Age-Related Context
- Testosterone levels naturally decline at approximately 1.6% per year starting in the mid-30s 3
- At age 45, your levels remain robust and do not reflect pathological decline 3
- Age-specific cutoffs for low testosterone in men aged 40-44 years is 350 ng/dL, well below your current level 4
Important Caveats
If You Have Symptoms
- If you're experiencing symptoms like decreased libido, erectile dysfunction, or fatigue, these are not due to low testosterone given your normal levels 1
- Approximately 20-30% of men receiving testosterone therapy inappropriately do not have documented low testosterone levels before treatment initiation 1
- Other causes should be investigated, including:
Measurement Considerations
- Your results should ideally be from a morning fasting sample (8-10 AM) when testosterone levels peak naturally 1, 3, 6
- If this was an afternoon or non-fasting sample, consider repeating in the morning for accuracy 3, 6
- A single measurement is generally sufficient when levels are clearly normal like yours, though diagnosis of deficiency requires two separate morning measurements 1, 3