Male Hormones: What they do and What to look for

Hormones are tiny molecules that float around in our bloodstream making big changes. Hormones can cause stress, appetite changes, growth, and so many more outcomes despite their small size. There are countless hormones in the body, and they are responsible for making us who we are to some extent. This poses a question. What hormones make a man a “MAN” and how can I test and read my results? Below I am going to go over three hormones and explain what they do, how you can test them, and what the results may mean.

Testosterone:

Testosterone, when you hear this you instantly think big muscles, body hair, and roid rage. While these are related to testosterone, there is a much more delicate balance taking place in the body. Testosterone is synthesized from a cholesterol building block, and this classifies it as a steroid hormone, or more specifically a sex hormone. Testosterone is mostly synthesized in the testes, and it follows a long pathway starting in the brain’s hypothalamus and pituitary gland. In the hypothalamus a hormone called gonadotropin releasing hormone (GnRH) is released and triggers the release of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary gland. The pituitary gland is known as the “master gland”, and is involved in many hormonal pathways in the body. LH is the hormone that is more directly related to testosterone production, so we will focus on tracking its path through the body. LH will eventually reach certain cells in the testes called “leydig cells”, and this is where the production of testosterone takes place. As testosterone is synthesized from precursors (most notably DHEA which you may find on hormonal supplement labels), it is spread throughout the body via the bloodstream. Interestingly, testosterone actually uses a phenomenon called “feedback inhibition” to regulate its production by inhibiting FSH, LH, and GnRH. What this means is that as more testosterone is produced, the production will decrease in order to maintain hormonal balance. Many testosterone boosters try to combat this by providing these hormones or compounds that imitate them. As testosterone spreads around the body, it can attach to different androgen receptors and produce the above mentioned effects (muscle growth/strength increase, body hair, etc.)

What are We Testing?:

When testing your testosterone, there are three main numbers you want to look at. These are total testosterone (the amount of testosterone you have), free androgen index (the amount of testosterone that is unbound and can spread throughout the body), and SHBG (sex-hormone binding globulin). All of these can be tested using an at home blood test you can purchase online. I don’t feel that total testosterone needs to be explained, it's simply how much testosterone is present. The other two values, however, could use some explaining. Free androgen index indicates how much of your testosterone is free and able to travel throughout the body and be used. Think of this like a vehicle with a governor. The total testosterone is the top limit of the speedometer (say 140mph) and the free androgen index is the governor or the usable testosterone. The higher the governor (free androgen index), the faster the vehicle goes (the higher % of usable testosterone). So what impacts this? That leads us to SHGB or sex-hormone binding globulin. SHBG is a glycoprotein (a protein with an attached carbohydrate chain) that binds up free testosterone. High levels of SHBG result in lower levels of free testosterone due to more testosterone being bound. Having lower levels of SHBG allows for the testosterone in your body to be more readily used, which is ideal. (SHBG is actually produced in the testes, but in another set of cells called the “sertoli cells” which create sperm in response to FSH.) So now that we know more about these three values, what are normal ranges of each?

Normal Ranges:

Total Testosterone (in adult men): 300-1000 ng/dl (it is normal for value to drop as you reach middle and old age)

Free Androgen Index: 30-130

SHBG: 10-57 nmol/L

Estradiol:

For every yin there is a yang, and that is the role estradiol plays in relation to testosterone. While they have very similar structures and some testosterone is even converted to estradiol in men, there should be a large discrepancy between the two levels in healthy individuals. In men, estradiol plays a role in sexual function. It can be used to increase the secretion of FSH from the pituitary gland, and in turn increase spermatogenesis in sertoli cells located in the testes. Estradiol also impacts erections and ejaculatory functions, and if levels become too high they can inhibit these functions and also lower sex drive. Estrogen has been a huge focus in men’s health in recent years as estrogen levels have risen in men over time. This is mainly attributed to chemicals used in food, beverage, and plastics that can imitate and modulate hormones. It is also talked about in gym culture as many lifters who have used substances that unnaturally increase testosterone were left with symptoms like gynecomastia due to hormone imbalances after usage of the aforementioned substances. It’s because of circumstances like these that measuring your estradiol is just as important as measuring your testosterone as the two perform a “hormonal tango” in the body.

Normal Ranges:

Estradiol (in adult men): 10-45 pg/ml (it is normal for value to increase with age)

Note: when testosterone begins to drop below normal range and estrogen begins to rise above normal range it may be time to make lifestyle changes/begin supplementation, be sure to consult with a health professional.

Prolactin:

Prolactin is probably the least known of the three hormones we are discussing, but being aware of your prolactin levels and how they can relate to the aforementioned hormones is crucial. Prolactin is most commonly known for its role in lactation and breastfeeding. It is the hormone that is released when a baby latches on to his mother’s nipple and it signals for milk to be released. In men, it is more so used to judge hormonal balance as elevated prolactin can cause lower levels of testosterone. Men with high levels of prolactin are more susceptible to erectile dysfunction, infertility, and oftentimes report lower sex drive. It is because of this that testing your prolactin is so important because it can oppose a lot of the things that we consider to make a man a “man”. Having elevated prolactin can be caused by things like sexual activity, stress, and poor sleep, so a slightly elevated level is not something to start writing your will over. There are some conditions associated with elevated prolactin in men, so sharing your results with a health professional is recommended if you see anything out of the norm.

Normal Ranges:

Prolactin (in adult men) 2-18 ng/dl

Note: High intensity exercise is associated with elevated prolactin, so if you workout hard 4-7 days a week it is normal to have a slightly higher result. I personally have a level in the 20’s that is most likely due to powerlifting focused weight training.

Sources:

Schulster, M., Bernie, A. M., & Ramasamy, R. (2016). The role of estradiol in male reproductive function. Asian journal of andrology, 18(3), 435–440. https://doi.org/10.4103/1008-682X.173932

https://militarymuscle.co/blogs/guides/how-to-lower-prolactin-for-bodybuilding#:~:text=This%20could%20be%20related%20to%20differences%20in%20program,shown%20to%20reduce%20prolactin%20levels%20in%20some%20studies.