It’s no big secret that male and female physiologies differ greatly. Physical appearance, skeletal structure, reproductive systems and even brain size differ between the two genders. Hormones play a vital role in these differences, as well as for the maintenance of overall health.
There are several hormones responsible for the majority of men’s health and wellbeing, especially for the healthy functioning of the reproductive system, bone health, libido support and the maintenance of lean muscle mass. Keep reading for more information on these hormones, including how they are produced and the specific roles they play.
How Are Male Hormones Produced?
The primary male sex organs are the testes – also known as the testicles or gonads, their role is to produce sex cells (sperm) and produce and secrete a variety of a man’s hormones.
Male hormones are known collectively as androgens and they play a vital role in the development and function of the reproductive organs, sexual behaviour and sexual drive. Androgens also influence the growth and development of many other organs and tissues of the body.
How do androgens come about? They are released at puberty. Puberty begins in boys (and in girls, too) when an area of the brain called the hypothalamus starts releasing a hormone called gonadotropin-releasing hormone, or GnRH for short. GnRH then travels to the pituitary gland, a small gland that sits under the brain, which causes the release of two additional hormones: luteinising hormone (LH) and follicle stimulating hormone (FSH). These hormones then travel through the blood stream to the testes and provide instructions for cells to start producing sperm and the most well-known male hormone, testosterone.
Male hormone production is also regulated by a special relationship between the hypothalamus, pituitary gland and gonads, known as the hypothalamic-pituitary-gonadal (HPG) axis. The adrenal glands that sit above the kidneys also secrete small amounts of these hormones.
Testosterone is mostly made by the testes, however small amounts are also produced by the adrenal glands, two pyramid-shaped glands that sit above the kidneys. Testosterone is also formed from another hormone called androstenedione, which is secreted by the testes and gets rapidly converted into testosterone.
Testosterone is important for sexual function and libido, as well as a range of other body functions and processes. In certain cells, testosterone gets converted into another type of hormone to exert its effects. In the prostate for example, testosterone gets converted into dihydrotestosterone (DHT) which supports the growth of the prostate gland.
During puberty, testosterone prompts the production of sperm and causes the growth and maturation of the penis, glands and ducts. At this time, it also promotes the growth of secondary sex characteristics like pubic and facial hair, deepening of the voice, increased sebum (oil) production, increased skeletal growth especially at the shoulders and the increase of lean muscle mass.
Testosterone also boosts a man’s basal metabolic rate, helping to maintain a healthy balance of lean muscle mass and fat stores.
Gonadotropin-Releasing Hormone (GnRH)
As mentioned above, GnRH is released at puberty and kick-starts the production of hormones required for the development of the reproductive system. GnRH does so by binding to the cells of the pituitary gland to stimulate them in order to release the gonadotropin hormones – they are known as luteinising hormone (LH) and follicle stimulating hormone (FSH).
Gonadotropin Hormones (LH & FSH)
- LH binds to the cells in the soft connective tissue around the seminiferous tubules (tightly coiled tubes that contain cells and lumen that help create sperm) in order to secrete testosterone and a small amount of oestrogen
- FSH enhances the production of sperm by stimulating cells to release a particular protein (called androgen-binding protein or ABP) which keeps the concentration of testosterone in the spermatogenic cells high
Inhibin is a hormone produced by cells called sustentocytes, they supply nutrients to the sperm. Inhibin acts as a kind of ‘regulator’ to control the production of sperm and associated hormones. When a man’s sperm count is low, inhibin levels drop significantly so that FSH can do its work in increasing sperm levels; and when a man’s sperm count is high, more inhibin is released which stops the production of FSH.
Oestrogen’s Role in Men’s Health
Oestrogen, like the other male hormones, is produced by the testes. It supports:
- Bone health – it’s involved in bone metabolism which helps prevent osteoporosis, plus also supporting joint health
- Lean body mass – in conjunction with testosterone, oestrogen helps to regulate appetite and support the growth and maintenance of lean muscle mass
- Heart health – oestrogen supports the health of the walls of the arteries
So there you have it! Men’s health is the result of a unique and complex relationship between specific organs and glands, in order to secrete crucial hormones that are involved in many body processes that keep men feeling and functioning at their best.
Marieb, E.N., Hoehn, K. (2013), Human Anatomy & Physiology, Chapter: The Reproductive System, pp. 1019-1034, Pearson Education Inc.
Hechtman, L. (2012), Clinical Naturopathic Medicine, Chapter: The Male Reproductive System, pp. 872-875, Churchill Livingstone, Elsevier