The hype around testosterone supplements clearly stems from cultural attitudes involving the exposure and celebration of athletes and, by extension, of masculinity. Individuals are susceptible to believing that a steady intake of hormone-boosting substances will bring upon themselves at least a fraction of their favorite athlete’s muscle complexion, strength, and general appeal. And the media scandals that inevitably erupt when some sports stars choose the controversial (and often illegal and dangerous) path of doping through hormone tampering only add to the attraction of the easy road to success.
The picture, however, is far more complicated than that. Throughout this article, we will take you through the history and chief medical uses of testosterone (i.e., rare and serious conditions), the importance and role of testosterone in the male body, while also discussing the main ingredients of available testosterone supplements and taking you through the methods of how and if these substances affect the normal processes involving testosterone in order to deliver on their claimed effects.
Testosterone – What It Is and How Does It Work?
Index of Contents
Common knowledge holds testosterone as the primary “masculine hormone”, possessing even powers of cultural outreach, in opposition to the feminine “primary hormone”, estrogen. If we are to delve deeper into the do’s and don’ts of supplementing one’s levels of testosterone, we should get to know more about its workings, if not its intricacies.
The General Perspective
It is a misconception that only men have testosterone in their bloodstreams because, as is the case with any substance, when an organism comes into contact with it, there are (usually minuscule) degrees of absorption. Testosterone is present in the organism of females as well as males, however, in much smaller proportions. Mammals have their first exposure to testosterone as fetuses, and humans get their first exposure in the first six weeks of pregnancy. The actions of the hormone in the pregnancy phase are not quite well understood, though it seems that adequate levels have some bearing in making up the sex and other characteristics of the fetus.
Moving on to the realm of certainties, glands are the organs of our bodies that produce testosterone, more specifically, they synthesize testosterone from cholesterol but more on that later. In both men and women, adrenal glands manufacture testosterone in barely noticeable amounts. At the cellular levels, the main producer of testosterone are Leydig cells, named after the anatomist who discovered them in 1850. The testicles display a large number of Leydig cells, therefore they secrete a high amount of testosterone, while the ovaries have a much smaller amount of this type of cells in their make-up.
Upon actions from the hypothalamus (the part of the central nervous system whose primary function is to control the endocrine system) through the pituitary gland, testicles begin to secrete increasingly larger amounts of testosterone during puberty. The amount remains relatively high until the man reaches his late 20’s. Around 30 years of age, human males start experiencing a decrease in testosterone levels, about 1 percent with every passing year. We have provided you with this little “endocrine interlude” because any dysfunction in the hypothalamus, the pituitary or further across the hormonal chain may result in abnormal levels of testosterone.
The growth in testosterone level at puberty is the one responsible for the changes of puberty and the in particular onset of the male secondary sex characteristics – body hair, facial hair, a deeper voice and a higher bone and muscle mass, at least when comparing the average male with the average female.
The effects that testosterone has (we are concerned with men here obviously) are more far-reaching than this. Where the reproductive system is concerned, testosterone controls various aspects such as sperm production (as an interesting digression, long-term hormone therapy has been linked to a decrease in the production of sperm), a man’s sex drive (with testosterone levels increasing during periods of sexual activity and levels lowering when inactive). When the levels are unduly low, men may experience erectile dysfunction. However, that is one of many possible causes of the dreaded problem. Be that as it may, it is important to note that not only levels of testosterone are important, but also their timing in an individual’s life because the reproductive and endocrine systems do not exist independently in a biological void.
When it comes to the central nervous system, we have explored the manner through which certain parts of the brain control the levels of testosterone production. If we consider that what goes around comes around, testosterone also influences certain behavioral aspects. A significant presence of testosterone has links with an increase in an individual’s aggression, competitiveness or self-esteem. As is the case with sexual desire (discussed above), taking part in competitive (mostly) physical activities boosts testosterone and, accordingly, the hormone’s absence may explain undesirable conditions such as lack of motivation which translates in affecting one’s ability to concentrate, states of mild depression or dysfunctions in the sleep pattern. Against this background, we should note that the reader must not hyperbolize these influences, mental dysfunctions have complex causes that are yet to be understood wholly. We are merely in the realm of favoring factors.
The growth of bodily and facial hair is a staple of testosterone’s effects during puberty. As mentioned above, a decrease in levels is normal from a certain age. An acceleration in this decrease usually leads to side-effects such as hair loss, acne, and enlargement of breasts. These unwelcome events can be treated through hormone replacement therapy. This is a delicate and complicated subject, which will be revisited in this article.
Bone and muscle growth is another result of the influence of testosterone. The hormone is an anabolic steroid because it stimulates neurotransmitters into increasing the protein in cells, a process that is best observed in the skeletal and muscular tissues. At the nervous level, testosterone increases the production of red blood cells in the bone marrow. There also is a reciprocal relationship between the body’s ability to burn fat and hormone levels. Consequently, problems associated with old(er) age – decrease in muscle density leading to a propensity for fractures or an abnormal weight gain – certainly have testosterone as a culprit and a remedy could be devised along these lines.
Testosterone’s relationship with the circulatory level is highly ambivalent. We have established that cholesterol is a precursor of testosterone, with the metabolism acting as a test tube for its production. Thus, raising and lowering the levels of the hormone in the blood stream has yielded conflicting results for scientists, almost mirroring the debates the community is experiencing regarding the beneficial and negative effects cholesterol has on the heart and cardiovascular system. Some studies regard testosterone as having pernicious effects on blood pressure as well as on the blood clotting process, while others pointed to positive outcomes due to the increase of red blood cells that a high level of testosterone accounts for.
The Cellular Level
For a better understanding of the intricacies of how testosterone supplements work, their advantages and their downsides, one should have at least a primary understanding of what is going on at the cellular level, the chemical processes that produce testosterone and how the hormone affects the complicated biological balance.
As stated in the previous sub-section, Leydig cells located in the gonads of both men and women are responsible for the production of the vast majority of testosterone. Women produce, on average, about 15 times less testosterone than men. Testosterone is an androgen hormone, being classified alongside a wide variety of others, associated with both male and female characteristics. They compose a class because they share a common carbon ring structure in their chemical make-up, three 6-carbon rings coupled with a 5-carbon ring. This particular ring structure is called stearine, hence their designation as steroids.
The (simpleton’s schematic) chain of biosynthesis in the case of testosterone starts with cholesterol (found in a significant number of nutrients) which is transformed into a sort of proto-hormone known as pregnenolone. This compound, under the influence of several types of enzymes, becomes dehydroepiandrosterone (DHEA for short), an intermediate substance that can be artificially manufactured and is the key to creating effective testosterone supplements, or progesterone, compounds which are further refined for the final product to arrive.
After testosterone is secreted, most of it (around 98 percent) is embedded in the framework of globulin and albumin, proteins that have the role of conserving it against the damaging effects of kidney and liver action, which also provide the means of transportation across the body. The fractional amount left is considered to be testosterone that is unbound, and the portion of hormone responsible for the radical physical changes and underlying ones we have mentioned in the previous sub-section. The action of this type of “free testosterone” is facilitated by its frequent mutations into DHT, an androgen that is exponentially more potent.
Many internal and environmental factors may tamper with the reserves of effective testosterone, but discussing them would be beyond the modest scope of this schematization.
Testosterone Supplements – When, Why and How?
As we have already mentioned, testosterone has many potential effects and scientists break them down into two broad categories: androgenic (relating to the physical traits that they promote) and anabolic (effects about the higher rate of protein synthesis which, in turn, leads to muscle growth).
Anabolic Steroids – Synthesizing Testosterone
In 1935, the hormone was isolated, and its artificial production could begin. Be that as it may, oral administration of testosterone initially turned out to be extremely ineffective because of its almost total destruction by liver enzymes and by absorption in the small intestine. Further developments led to the creation of anabolic steroids, which are highly potent derivates of testosterone, put into a layman’s wording. For example, dihydrotestosterone (DHEA) is the agent that stimulates androgen receptor while bypassing the actions undertaken in a usual metabolization.
The aforementioned bypass means that side effects of these anabolic products can affect many major organs, thus having a very limited use. At first, their use was restricted to patients with late-onset puberty and for individuals with major muscle atrophy due to complicated surgeries. The severity of the reactions to anabolic steroids depends on a multitude of factors, ranging from the duration of its use, the dosage administered to individual toleration to the product, which is wildly fluctuating. Given that, administration of testosterone derivates for extended periods of time can negatively impact health – it could be something as mild as a propensity toward tendon ruptures to extensive psychological, reproductive, endocrine and even hepatic and cardiovascular damage.
Generally Available Supplements
As this warning from the FDA (and there probably are hundreds other similar warnings from similar agencies in the developed world) urges the public to consider the fact that prescription testosterone should be used only in cases where the patients have had a history of severe hormonal imbalances. This is because the dosage of testosterone is a very delicate affair, with the patient’s personal history to be taken into account, not just a matter of individual trial and error.
This is why the vast majority of supplements available on the market today probably contain just traces of the synthesized hormone, with the bulk of substances that claim to enhance masculinity being precursors of testosterone. The main problem with these precursors is that they walk a blurred line where the scientifical tests are yet to be undertaken and for these substances (at least for now) there are no clear chains of conversion such as the ones presented above. Nevertheless, we will attempt to review the ingredients these supplements claim to boost testosterone and see how they fare with the limited results at our disposal.
- Tribulus Terrestris is a herb indigenous to the Indian subcontinent and its properties regarding a boost in virility have a long tradition, dating back to the sacred texts of Hinduism. Unfortunately, only one serious study on humans exists, however, it backs up the preliminary results from rodent trials – increase in sex drive and alleviation of erectile dysfunction. Nevertheless, it seems that these results owe more to the actions this plant has on the cardiovascular system (tribulosin, the agent the herb contains, protects the heart muscle and blood vessels) because no discernible elevation in the levels of testosterone has been noticed in either rodents or humans.
- D-Aspartic Acid (D-AA) is a variation of the aspartic acid amino acid, which has and currently is still showing promising results in the boost of testosterone levels, especially in the case of males with marked deficiencies. Most specialists agree that it provides minor testosterone elevations in healthy males, with one study across 12 days using a relatively high dosage of D-AA garnering a mean testosterone increase of 42 percent. Similarly, athletes using D-AA report better results for short periods of time. Be that as it may, a continuation of administration results in a lowering of testosterone levels after about 15 days, with a return to normal levels after more than one month. As is the case with Tribulus Terrestris, results are relative regarding infertile men, yet the short span of testosterone increase in healthy men means it is not nearly enough for durable muscle growth.
- Magnesium and Zinc – these two minerals are crucial for the maintenance of adequate levels of testosterone, due to their being an integral part of the make-up of globulin and albumin. They are lost through sweating, be it caused by exercise or disease; therefore zinc and magnesium supplements may play a role in cases of testosterone deficiency, however, normal levels of the hormone do not get elevated through a further intake of minerals.
- Fenugreek (or Trigonella Foenum-Graecum) is a plant native to India and the Arabian Peninsula, popularly thought to increase libido. There is some truth to the claim that it may increase the levels of testosterone, yet that seems to be only a consequence of its properties in normalizing the metabolism of glucose because there exists a scientifically established link between diabetes and drops in testosterone levels. Fenugreek’s positive influences on the hormonal configuration are more far-reaching – constant inclusion in the diet of a recent mother supposedly stimulates breast milk
- Vitamin D – the current reputation of vitamin D as a booster of testosterone levels lies with a decade-old study implicating overweight men. The increase was noticeable, somewhere along the lines of D-AA, though a similar test for healthy men is yet to be undertaken. Sparse results in a single segment of the population mean the jury is still out on the propensity vitamin D has in upsurging virility.
- Mucuna Pruriensis is a plant known for being a great source of L-DOPA, a substance that is the immediate precursor of dopamine. Elevating the levels of dopamine in the bloodstream, and especially in the cortex is well known to increase one’s sex drive, with gender being irrelevant. A far-fetched connection is sometimes made between dopamine and prolactin (a compound that negatively influences testosterone levels) – dopamine counteracts the effects of prolactin, yet healthy males never have a pernicious presence of prolactin; therefore consumption of this plant could be advised only in the context of certain dysfunctions.
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