Free testosterone is the amount of testosterone in the body that is available to the cells and tissues. It is considered the active form of testosterone and plays a key role in vital bodily functions like bone density, muscle mass, strength, energy levels, libido, and cognition.
Some key points about healthy free testosterone levels:
- Free testosterone levels peak in most men during their late teens to early 20s, after which they slowly decline with age
- There is no universally agreed upon "optimal" level - reference ranges vary between labs and testing methods
- In general, experts suggest ideal free testosterone levels for adult men fall between the following ranges:
- Young men (age 20-39): Approx 9 - 26 pg/mL (nanograms per deciliter)
- Middle aged men (age 40-59): Approx 6.6 - 18 pg/mL
- Older men (age 60 ): Approx 4.5 - 14 pg/mL
- Men with levels below the reference range may have symptoms like low energy, reduced muscle mass, difficulty building strength, excess body fat, poor concentration, and low sex drive
Factors that impact free testosterone levels include:
- Age
- Fitness level and activity
- Weight/body fat percentage
- Quality of sleep
- Stress levels
- Certain medical conditions
- Use of particular medications
Some symptoms of
low free testosterone can include:
If low free testosterone is suspected, testing should include not only free T, but also total testosterone, SHBG (binds to T),
estradiol (the most potent
estrogen), thyroid hormones, and pituitary hormones.
A physician specializing in hormones and aging, like those at Hormone Harmony Clinic(), can properly diagnose the cause of low T after thorough lab testing and clinical evaluation. They can then create customized treatment plans involving lifestyle changes, supplements, bioidentical hormone therapy, or TRT to help men optimize their free testosterone levels.
Now back to reference ranges. Some key
general guidelines suggested by integrative physicians include:
- Men under 40: Free testosterone levels above 15 pg/mL are generally considered optimal
- Men 40-60 years old: Levels between 8-15 pg/mL are usually the functional target
- Men over 60: Aim for maintaining free test levels above 5 pg/mL or at least 50% of youthful levels for that lab
The ranges are meant as guides only, since
optimal levels differ between individuals based on genes, lifestyle and health status.
For example, some men feel their best at free T levels above 20 pg/mL, whereas others do well at just 10 pg/mL.
Working closely with an age management doctor for testing and treatment helps men achieve their unique peak balance for vitality and performance.
