This has become a common practice despite an Institute of Medicine (IOM) report issued in 2003, indicating insufficient evidence of any benefit derived from testosterone hormone therapy to address expected symptoms of male aging.4 These studies, and 2 others (to be presented in a separate EW research brief) come on the heels of research on the efficacy of prescribing testosterone5 that appeared in the NEJM last year.
Two of the immediate metabolites of testosterone, 5α-DHT and estradiol, are biologically important and can be formed both in the liver and in extrahepatic tissues. Approximately 5 to 7% of testosterone is converted by 5α-reductase into 5α-DHT, with circulating levels of 5α-DHT about 10% of those of testosterone, and approximately 0.3% of testosterone is converted into estradiol by aromatase. 5α-Reductase is highly expressed in the male reproductive organs (including the prostate gland, seminal vesicles, and epididymides), skin, hair follicles, and brain and aromatase is highly expressed in adipose tissue, bone, and the brain. As much as 90% of testosterone is converted into 5α-DHT in so-called androgenic tissues with high 5α-reductase expression, and due to the several-fold greater potency of 5α-DHT as an AR agonist relative to testosterone, it has been estimated that the effects of testosterone are potentiated 2- to 3-fold in such tissues.
The FDA approved testosterone therapy only for men having a low testosterone (hypogonadism) as the result of a diagnosed medical condition (ie, genetic defects), or as a side effect of cancer chemotherapy.3 However, testosterone frequently has been prescribed off-label to men who have had no diagnosed medical condition, other than an age-related decrease in circulating testosterone, also known as “low T”.
In order to discuss the biochemical diagnosis of hypogonadism it is necessary to outline the usual carriage of testosterone in the blood. Total serum testosterone consists of free testosterone (2%–3%), testosterone bound to sex hormone binding globulin (SHBG) (45%) and testosterone bound to other proteins (mainly albumin −50%) (Dunn et al 1981). Testosterone binds only loosely to albumin and so this testosterone as well as free testosterone is available to tissues and is termed bioavailable testosterone. Testosterone bound to SHBG is tightly bound and is biologically inactive. Bioavailable and free testosterone are known to correlate better than total testosterone with clinical sequelae of androgenization such as bone mineral density and muscle strength (Khosla et al 1998; Roy et al 2002). There is diurnal variation in serum testosterone levels with peak levels seen in the morning following sleep, which can be maintained into the seventh decade (Diver et al 2003). Samples should always be taken in the morning before 11 am to allow for standardization.
Maybe someone could help me out here. I am a 21 year old former college football player and have been experiencing low test for a while now, about a year ago i went in to see my doctor, and after becoming an expert over the subject thanks to the internet, i told him that i thought it had to be my testosterone level. So he had me come back the next day and got a level of 107ng/dL. He was shocked to say the least. He referred me to an IDIOT endocrinologist, and he which tested me again and got a level of 187. He said to do nothing for the next 3 MONTHS and levels should be 700-900… Yeah well about 4 months later, which was last week, i had to go in, there is some serious shit wrong with me, physically, mentally, you name it. The level came back at 57ng/dL… They said we need to run further tests… WTF is going on, i am dying here. What do i do people???
Testosterone may fight depression. If you’ve been battling the black dog of depression, it may be because of low testosterone levels. Researchers have found that men suffering from depression typically have deficient testosterone levels. While scientists haven’t been able to figure out whether it’s low testosterone that causes depression or if depression causes low T levels, preliminary research has shown that some men suffering depression report improvement in mood and other factors of depression after undergoing doctor-directed testosterone treatments.
Don’t waste your time with the gel, the Injectable is far superior. Also most will be given 200 mg cypionate per week, you can actually go much higher and feel a lot better and if combined with good resistance training and cardio achieve a very good figure and low fat percentage . There was actually a study overseas that said men could benefit with TRT at 600mg per week, although you will never see that happen with American doctors .
Testosterone levels generally peak during adolescence and early adulthood. As you get older, your testosterone level gradually declines — typically about 1 percent a year after age 30 or 40. It is important to determine in older men if a low testosterone level is simply due to the decline of normal aging or if it is due to a disease (hypogonadism).