Testosterone governs and controls everything sexual going on in your body. Therefore, adequate levels of testosterone are necessary in order to get erections, to avoid erectile dysfunction and to have a strong libido.
In men, testosterone also plays an important role in the development of male characteristics such as muscle mass, bone growth, body hair, and a deeper voice.
It also promotes certain kinds of behavior such as competitiveness, risk-taking, and dominance.
Testosterone is also very important for overall health and well-being.
More About Testosterone
Androgens stimulate and control the development and maintenance of male characteristics and sexual development.
Where is testosterone made?
Levels of testosterone are about 10 times greater in adult males than in adult females. And as the consumption of testosterone in males is greater, the daily production is about 20 times greater in men.
- Free testosterone: This is testosterone in its optimal and purest form. The reason it’s called ‘free’ is because it isn’t attached to any proteins. Unbound to other molecules, free testosterone can go about carrying out its functions freely by entering cells and activating receptors. Free testosterone normally makes up only 1-3% of a man’s total testosterone levels.
- SHBG-bound testosterone: About 40-50% of a man’s total testosterone is bound to a protein called sex hormone-binding-globulin (SHBG). SHBG is produced mostly in our livers and plays an important role in regulating the amount of free testosterone in our bodies. SHBG binds to testosterone in order to transport it to somewhere in the body where it can be used, or simply for storage for later use. While testosterone is bound to SHBG it is biologically inert.
- Albumin-bound testosterone: The remainder of our testosterone is bound to a protein called albumin. It is bound to albumin for the same reasons: transport and storage. Albumin is also produced in the liver, and its job is to regulate blood pressure by binding to water, fatty acids, hormones and a number of other compounds. Like SHBG-bound testosterone, albumin-bound testosterone is biologically inactive. However, unlike SHBG-bound testosterone, the bond between albumin and testosterone is weak and can be easily broken in order to create free testosterone when needed.
How Is Testosterone Produced?
This hormone makes its way over to the pituitary gland in the back of the brain. When the pituitary gland detects the gonadotropin-releasing hormone, it starts producing a hormone called luteinizing hormone.
When the brain detects that there is enough testosterone in the blood, it signals the pituitary gland to stop secreting luteinizing hormone so that the testicles can slow down or stop testosterone production.
Testosterone production takes place primarily at night when the body is sleeping.
This manufacturing of testosterone normally peaks about three hours into the sleep, and also normally continues for as long as a person is sleeping.
Therefore, testosterone levels are typically highest in the morning right after a person wakes up, and are also normally lowest in the evening before bedtime.
Also, in order to produce adequate levels of testosterone, it is paramount to sleep enough. If you only get 5 hours of sleep instead of 7 hours, you are likely to produce less testosterone than optimal.
The Link Between Testosterone, Erections, Libido And Erectile Dysfunction
Let’s find out.
First of all, testosterone is the fuel that makes sex possible. Testosterone regulates, controls and supports the sexual functions. Testosterone is simply crucial in order for your sexual organs to work and in order for your body to desire sex.
A healthy amount of testosterone enables you to have sex.
When the penis is in a flaccid state, the smooth muscles in the penis are in a state of contraction and therefore clench around the blood vessels.
When this happens, blood is squeezed out of the penis and the only blood that is allowed to enter is for maintenance purposes.
In order for a penis to become erect, blood needs to flow into the penis to fill it to its capacity.
Nitric oxide, when crated by the enzyme nitric oxide synthase, is diffused into the smooth muscles of the penis and make these smooth muscles start to relax and therefore give up the tight grip around the blood vessels.
When this happens, blood is allowed to flow into the penis and an erection can be built.
Studies on animals and humans have shown that castrated individuals (castration will normally lead to a significant reduction in testosterone production) tend to lose a significant amount of nitric oxide synthase activity compared to uncastrated individuals.
And why is dopamine so important?
When you are sexually stimulated, dopamine is produced in your brain, then travels down your spinal cord and to your penis. Here it instructs nitric oxide to be produced so that the muscles in your penis can relax and so your penis can be filled with blood.
In other words, if there is a lack of testosterone over a significant period of time, a person may experience a decay of integral features of the penis – the penis may stop working properly – and erectile dysfunction may kick in as a result.
The Roles of Testosterone
In very young boys, testosterone impacts brain development leading to development of characteristics such as high levels of activity, increased risk taking, exploration, need for dominance, etc.
In late childhood, testosterone contributes to the growth of pubic hair, axillary hair, facial hair, increased oiliness of skin and hair and acne formation.
Boys will often also witness a sudden growth and lengthening of arms and legs due to bone maturation just before reaching adolescence.
During adolescence, testosterone makes boys acquire a deeper voice, makes facial features take on a more defined contour, increases muscle mass, makes shoulders broader, makes hair growth increase overall, and makes the Adam’s apple appear.
Also during adolescence, testosterone will also cause young men to experience an increase in sexual desire.
And during adulthood, one of testosterone‘s key functions is to regulate sperm production.
Testosterone also plays a role in development of certain behaviors, including aggression, dominance, tolerance for risk-taking and the desire for power.
It also helps to spark competitiveness, increase self-esteem and contribute to higher levels of energy.
Testosterone And Aging
Testosterone levels peak in the late teens and then gradually decline over time, typically by about 1% a year after age 30.
By age 60 to 65, though usually earlier, most men notice that their sexual desires and sexual abilities have changed; it takes longer for the penis to become erect and erections may not be as firm as before.
It may also take longer to achieve orgasm and to ejaculate.
Erectile dysfunction also becomes more common.
In addition to the impact on sexuality, the decline in testosterone plays an important role in a series of signs and symptoms that accompany the ageing process, such as a decline in muscle mass, strength and bone mass (osteoporosis) as well as an increase in abdominal fat.
Testosterone and Cholesterol
The body can obtain cholesterol from animal-based foods, but it’s also made as needed by the liver and intestines.
You need cholesterol.
For instance, an important role of testosterone is to enable and support high-density lipoproteins in the removal of excess cholesterol from the arteries and transport it to the liver for destruction.
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