Testosterone is one of the types of male hormones that can freely circulate in the blood or combine with proteins. Being one of the most important for the male body, it is responsible for the formation of sexual characteristics, sexual desire, as well as a number of other functions. In the body of a healthy man, free testosterone is contained in a certain amount, and if it is elevated or lowered, it leads to metabolic disorders, impotence, nervous and vascular diseases.
What is free testosterone – a detailed information
The difference in testosterone concentration in the blood is associated with age, as well as the time of day when a blood test is taken. The maximum level is observed between 4 and 8 o’clock in the morning. The minimum level is found between 16 and 20 pm.
It seems that it is enough to take blood tests for total testosterone to find out whether it is decreased or elevated. However, it’s not all so simple. What is the difference between free and total testosterone?
What is free testosterone?
Testosterone, which is formed in the testicles and adrenal glands, enters the bloodstream. Once the formed hormone called total testosterone (100%) enters the blood, the bulk of it is picked up by blood proteins (98%), and a few percent remain free (2%). Testosterone binds to two kinds of proteins: sex hormone-binding globulin (60%) and albumin (38%). The association with albumin is not stable, so this part of testosterone is referred to as a free form. This is the main difference between the two forms.
The hormone bounded with the globulin is inactive, while testosterone free is the active fraction of total testosterone (T total), and it has various effects on the body, is responsible for sexual behavior, as well as for male sexual characteristics. If according to the results of the tests, the levels of total testosterone are normal, this is not a 100% evidence of the absence of problems with the production of hormones. The normal total rate is not a characteristic of the norm of the active form, which directly affects the male body.
The main difference between the analysis of various forms of substance is the fact that the T common can hide the lack of an active form. Therefore, a separate free T-test is needed.
The level of sex hormone-binding globulin affects the ratio of free TS to estradiol. Normally, this ratio is in equilibrium. If a man has a higher globulin level, then they bind more free testosterone. This, in turn, leads to a change in the ratio in favor of estradiol. Consequently, the man will develop effects of the negative influence of female sex hormones.
Free testosterone levels – the norm
Free testosterone levels in men depend on the age and time of day. The highest rate of this hormone is observed in men from 15 to 50 years. Also, doctors note peaks of activity in the morning hours and a decrease in the norm in the evening; this fact is necessarily taken into account when giving blood for free testosterone in men. The hormone content in the body is calculated in nmol/l, and its normal value depending on the age is presented below.
Age-related free testosterone chart in men:
1) age under 1- 0-17.
2) 1-6 years old – 0-1.51.
3) 6-11 years old – 0.39-2.01.
4) 11-15 years – 0.48-22.05.
5) 15-18 years – 3.61-37.67.
6) 18-50 years – 5.76-30.43.
7) 50-90 years – 5.41-19.54.
Free testosterone range is usually lower in women.
Differences between the limits of the normal level of the hormone in the male body are explained by many factors. First of all, these are diurnal fluctuations, but the norm is also influenced by sexual activity, nutrition, exercise or lack of activity, past illnesses and a number of other factors, such as using non legal steroids. These factors can increase the level of the hormone or decrease it.
Features of the tests for determining the free testosterone range
To obtain reliable results of the test on the level of total and free testosterone, several conditions must be fulfilled. Analysis for testosterone is given after special preparation, if it is not observed, the results will be incorrect. For two days, it is desirable to exclude physical and emotional stress. A few hours before the analysis it is forbidden to eat and take tablets, drink alcohol and smoke. It is advisable to take the analysis before noon to see an adequate concentration of T hormone. Also, to assess the real level of the hormone and not to get a huge difference between the rates, some experts recommend taking the test twice.
The test is carried out according to certain indications. If a man has signs of a pathology of target organs for testosterone, then the test for free testosterone is mandatory. These signs include a violation of potency, infertility, acne, osteoporosis. The analysis of free testosterone is prescribed with a delay or early puberty in boys. However, to date, very rarely a doctor assigns an analysis only to the level of the general T.
The results of the study may be influenced by the intake of medical pills, physical exertion. Venous blood is taken for the test. The volume of the blood depends on the laboratory and the variants of testing methods. More and more scientists speak of the possibility of using saliva to determine the level of free T. The level of free T in saliva does not depend on the concentration of proteins. According to the results of the test, it will not differ in saliva and in plasma. However, not all laboratories can perform a test using saliva.
Best free testosterone booster – Tribulus terrestris
Tribulus terrestris is the most popular component of testosterone boosters. It has the largest evidence base and is available in almost every T booster. It is often referred to as natural steroids. The most popular and the best free testosterone booster supplement that contains Tribulus is Brutal Anadrol.
However, due to the lack of scientific confirmation of the effectiveness of this additive, we can not recommend Tribulus terrestris for muscle mass gain. However, as a component in complex supplements, it can be useful for men with low levels of testosterone, such as athletes with a risk of overtraining syndrome, as well as people adhering to the prolonged low-calorie diet. The most effective testosterone booster is anabolic steroids, such as Nandrolone. However, they can disrupt the normal hormonal background and cause harm to health. The same goes for synthetic human growth hormone.
Unfortunately, sometimes, steroids and sport are inseparable concepts. It is especially true for professional bodybuilding. However, athletes use not only steroids. They take anti-estrogens (such as Clomid), synthetic fat burners such as Clenbuterol, and others.
Free testosterone calculator – calculate your hormone levels online
On some sites, you can calculate the level of free testosterone using data from other tests.
With the help of free testosterone calculator, you can easily calculate the bioactive testosterone circulating in the blood plasma. These parameters can more accurately reflect the level of free T hormone than the sole measurement of total serum T hormone does.
To calculate free testosterone with a calculator, you need to know:
- albumin levels;
- SHBG levels;
- total testosterone levels.