On bodybuilders and some medical forums people can now notice the abbreviation TRT more frequently than they’ve seen before. TRT stands for Testosterone Replacement Therapy and is used for increasing testosterone levels in patients who have low levels of it.
What is Testosterone and what does it do?
Testosterone is the primary male sex hormone that promotes the development of prostate and testes during puberty and secondary male sex characteristics. It also stimulates bone and muscle growth.
Some other functions of testosterone are regulation of cholesterol, blood sugar, mobilization and breakdown of fat lipolysis and maintaining the immune system.
Most of it is produced by so called Leydig’s cells in the testes and a small amount (about 5% total) is produced by the adrenal glands.
There are two types of testosterone in a man’s body: bound and free testosterone. Bound testosterone is about 98% of total testosterone. 2% of testosterone is free and biologically active.
Can low testosterone make you fat?
There is not a confident answer on that question. A study, presented at the European Congress on Obesity, showed that patients with higher testosterone levels lost in average 35 pounds each, however, they doubt that it was a direct effect of testosterone.
Scientists believe that men with low testosterone have obesity because of their low energy, exhaustion, fatigue and non-active lifestyle.
So after patients have used TRT to normalize their testosterone level they just became more active and lose weight only for this reason.
What are normal testosterone levels?
Testosterone levels in blood are changing throughout the whole man’s life. It’s the highest during puberty and its production declines during mid and old age.
Also, results may vary as different laboratories may use different methodologies and assays to measure the level of free testosterone. For example, you can always order lab tests online and here is testosterone test cost in different online lab stores.
About 20-40% of older men have low testosterone and suffer from changes in sleep patterns, fatigue/exhaustion, decrease in muscle mass, weight gain, hair loss and depression caused by low testosterone levels.
The free testosterone level is as important as the total amount of testosterone in the blood. Some health care providers are confident that free testosterone could be even more important than a total amount.
The normal range for free testosterone levels in men in different periods of life is presented in the following table:
Age, years |
Min. Testosterone level, ng/dL |
Max. Testosterone level, ng/dL |
| 15 | 1.62 | 17.7 |
| 16 | 2.93 | 19.5 |
| 17 | 4.28 | 20.9 |
| 18 | 5.40 | 21.8 |
| 19 | 5.36 | 21.2 |
| 20 – 25 | 5.25 | 20.7 |
| 25 – 30 | 5.05 | 19.8 |
| 30 – 35 | 4.85 | 19.0 |
| 35 – 40 | 4.65 | 18.1 |
| 40 – 45 | 4.46 | 17.1 |
| 45 – 50 | 4.26 | 16.4 |
| 50 – 55 | 4.06 | 15.6 |
| 55 – 60 | 3.87 | 14.7 |
| 60 – 65 | 3.67 | 13.9 |
| 65 – 70 | 3.47 | 13.0 |
| 70 – 75 | 3.28 | 12.2 |
| 75 – 80 | 3.08 | 11.3 |
| 80 – 85 | 2.88 | 10.5 |
| 85 – 90 | 2.69 | 9.61 |
| 90 – 95 | 2.49 | 8.76 |
| 95 – 100+ | 2.29 | 7.91 |
People use different methods and testosterone replacement therapy (TRT) and some other methods in order to increase the testosterone level. Some of the most popular of them are testosterone injections and pellets (implants).
Are testosterone injections safe?
Testosterone injections are one of the most popular and effective ways to increase testosterone in the body.
This method involves the oil-based testosterone injection into the muscle, where it is absorbed into the blood stream over time. The recommended dosing regimen is 100 mg every week or one injection every two weeks if the dose is 200 mg.
Patients who use testosterone injections should consider that testosterone levels may exceed normal levels several days after the injection and increase red blood cell production more than other forms of testosterone.
Testosterone injections are inexpensive and considered to be relatively safe. Of course, testosterone should be obtained at a licensed local pharmacy. Otherwise, it can be contaminated and cause different adverse effects.
Are testosterone injections legal?
Testosterone is classified as a controlled substance under Anabolic Steroids Control Act of 1990 by the Drug Enforcement Agency.
So, it is important to know that it is illegal to obtain testosterone, and it is illegal to make an injection of it without a prescription from primary care doctor or other health care professional.
Are testosterone pellets effective?
The other option for people who have to use TRT is to use testosterone pellets that are implanted underneath the patient’s skin by a physician. Pellets slowly release testosterone over a 3-6 month treatment period.
Pellets need only about a 1cm incision to be inserted and they are only 3-9mm long. Typically, doctors insert them into the upper buttock area or lower abdominal wall.
This method is convenient for people who don’t wish to administer their medications, take pills or make frequent testosterone injections.
One of the advantages of using testosterone pellets is that they provide relatively steady testosterone levels throughout a course of TRT for those who wish to increase their testosterone level effectively.
Are testosterone pellets safe?
During the procedure, about 10 pellets are implemented underneath the skin. The procedure itself is considered to be safe.
Sometimes, pellets can be extruded and come out of a patient’s skin. However, this is rare. 0.6% of cases result in infection and about 8% result in extrusion.
Patients should also be aware of the correct dose before the implementation, so it is a good idea to use creams and patches to find the correct dosage.
Other options
Pellets and injections are only a few methods that can be used. They are the most popular and effective.
However, the market of testosterone solutions is still growing and now patients with “low T” can also find topicals and gels that may help in TRT as well as some other oral solutions.
They are different in their price and effectiveness and in any case patient should get a consultation from a doctor about what kind of TRT will be the most effective in terms of cost, time, and safety.
