Testosterone is a hormone that plays a crucial role in the development and maintenance of male sexual characteristics and reproductive functions. It belongs to a class of hormones known as androgens. While it is primarily produced in the testes in males, smaller amounts are also produced in the adrenal glands.
Testosterone is responsible for a wide range of physiological functions in males, including:
- Anabolic Effects: Promoting the development of muscle mass, bone density, and overall body composition. It aids in the growth and repair of tissues, contributing to physical strength and vitality.
- Androgenic Effects: Related to the development of things like the growth of facial and body hair, deepening of the voice.
- Reproductive Function: Testosterone is crucial for sperm production (spermatogenesis) and supports male fertility. It also plays a role in sexual desire (libido) and erectile function.
It also plays a significant role in psychological functions as does all hormones. Primarily affecting mood, energy, and overall sense of well-being with its strong connection with dopamine and motivation.
While testosterone is primarily associated with males, it's also present in smaller quantities in females, where it contributes to functions like maintaining bone density, supporting muscle mass, and influencing libido. Maintaining balanced testosterone levels is essential for overall health and well-being in both males and females. Though we are only going to focus on males for the rest of the series.
HOW TO GET YOUR TESTOSTERONE LEVELS CHECKED?
Getting your testosterone or androgen profile tested generally involves a simple blood draw, however they usually only test for total testosterone and potentially thyroid without too many questions. However, if you want a full panel, you will most likely need to finesse the doctors as currently in Australia they do not automatically put all these down due to extra costs and restricted funding from the government. A full panel will include things like your Total Testosterone, Free Testosterone, Bioavailable Testosterone, Sex Hormone Binding Globulin (SHBG), Dihydrotestosterone (DHT), Luteinizing Hormone (LH), Follicle-Stimulating Hormone (FSH), and Insulin-like Growth Factor-1 (Igf-1). This will depend on the clinic, pathology, and doctor you have.
Total Testosterone: Refers to the overall amount of testosterone in the bloodstream, including both free and bound forms.
Healthy Range (Adult Males): Roughly 300 to 1000 nanograms per decilitre (ng/dL) or 10.41-34.7 nanomoles per litre (nmol/L).
Bioavailable Testosterone: Represents the portion of testosterone that is both free and loosely bound to albumin and is readily available for use by cells.
Healthy Range (Adult Males): About 83 to 257 nanograms per decilitre (ng/dL).
Sex Hormone Binding Globulin (SHBG): Is a protein that binds to sex hormones (testosterone, estradiol, & DHT), regulating their availability in the body.
Healthy Range (Adult Males): Typically, 10 to 50 nanomoles per Litre (nmol/L).
Free Testosterone: Is the portion of testosterone not bound to proteins in the blood and is available for use by the body's tissues.
Healthy Range (Adult Males): Approximately 5.0 to 21.0 picograms per millilitre (pg/mL).
Insulin-like Growth Factor-1 (IGF-1): Is a hormone involved in cell growth and development.
Healthy Range (Adult Males): For adult males, it's around 116 to 358 nanograms per millilitre (ng/mL).
Dihydrotestosterone (DHT): Is an androgen, derived from testosterone, that plays a role in male sexual development (Hair growth, deepening of the voice, penis growth, erections, etc)
Healthy Range (Adult Males): Approx 10% of your testosterone converts to DHT daily.
Luteinizing Hormone (LH): Is a hormone that signals the testes to produce testosterone.
Healthy Range (Adult Males): Normally 1.24 to 7.8 international units per litre (IU/L).
Follicle-Stimulating Hormone (FSH): Is a hormone that stimulates the production of sperm in the testes.
Healthy Range (Adult Males): Typically, 1.27 to 19.26 international units per litre IU/L.
Conversion: 1 nanomoles per litre (nmol/L) is approximately 28.85 nanograms per millilitre (ng/mL).
A simple yet incomplete way to look at all of this as the human body is complex and research is very limited or insufficient, is that the primary function of the things mentioned above with the physiological functions of testosterone are.
- Free Testosterone and IGF-1: Mainly involved in anabolic effects.
- DHT: Primarily associated with androgenic effects.
- LH and FSH: Mostly involved in reproductive effects.
Continue to TESTOSTERONE: THE DETRIMENTAL DECLINE