Testosterone — What It Does And Doesn't Do
Aug 29, · Testosterone is the major sex hormone in males and plays a number of important roles, such as: The development of the penis and testes The deepening of the voice during puberty The appearance of facial and pubic hair starting at puberty; later in life, it may play a role in balding. Testosterone is a sex hormone that plays important roles in the body. In men, it’s thought to regulate sex drive (libido), bone mass, fat distribution, muscle mass and strength, and the production of red blood cells and sperm. A small amount of circulating testosterone is converted to .
When you think of testosterone, what comes to mind? Macho men? Aggressive, impatient, type A behavior? Road rage? Testosterone's role in bad behavior is largely a myth. What's more, testosterone plays other important roles in health and disease that may surprise you. For example, did you know that testosterone is a key player in prostate cancer? Or, that women need testosterone, too? There's more to testosterone than guys behaving badly. Adolescent boys with too little testosterone may not experience normal masculinization.
For example, the bpdy may not enlarge, facial and body hair may be scant and the voice may not deepen how to take care of yourself when pregnant. Testosterone may also help maintain normal mood. There may be other important functions of this hormone that have not yet been discovered.
Signals sent from the brain to the pituitary gland at the base of the brain control the production of testosterone in men.
The pituitary gland then relays signals to the testes to produce testosterone. A "feedback loop" closely regulates the amount of hormone in the blood. When testosterone levels rise too high, the brain sends signals to the pituitary to reduce production. If you thought testosterone was iis important in men, you'd be mistaken.
Affecy is produced in the ovaries and adrenal gland. It's one of several androgens male sex hormones in females. These hormones are thought to have important effects on:. The proper balance between testosterone along with other androgens and estrogen is important for the ovaries to work normally.
While the specifics are uncertain, it's possible that androgens also play an important role in normal brain function including mood, sex drive and cognitive function. Testosterone is synthesized in the body from cholesterol. But having high cholesterol doesn't mean your testosterone will be high. Testosterone levels are too carefully controlled by the pituitary gland in the brain for that to occur. Having too much naturally-occurring testosterone is not a common problem among men.
That may surprise you given what people might consider obvious evidence of testosterone excess: road rage, fighting among fathers at Little League games and sexual promiscuity. Part of this may be due to the difficulty defining "normal" testosterone levels and "normal" behavior.
Blood levels of testosterone vary dramatically over time and even during the course of a day. In addition, what how to install a spy app on iphone seem like a symptom of testosterone excess see below may actually be unrelated to this hormone. In fact, most of what we know about abnormally high testosterone levels in men comes from athletes who use anabolic steroids, testosterone or related hormones to increase muscle mass and athletic performance.
Among women, perhaps the most common cause of a high testosterone level is polycystic ovary syndrome PCOS. This disease is common. The ovaries of women how to test http post requests PCOS contain multiple cysts.
Symptoms include irregular periods, reduced fertility, excess or coarse hair on the face, extremities, trunk and pubic area, male-pattern baldness, darkened, thick skin, weight gain, depression and anxiety.
One treatment available for many of an problems is spironolactone, a diuretic water pill that blocks the action of male sex hormones. Women with high testosterone levels, due to either disease or drug use, may experience a decrease in breast size and deepening of the voice, in addition to many of the problems men may have. In recent years, researchers and pharmaceutical companies have focused on the effects of testosterone deficiency, especially among men. The testes produces less testosterone, there are fewer signals from the pituitary telling the testes to make testosterone, and a protein called sex hormone binding globulin SHBG increases with age.
All of this reduces the active free form of testosterone in the body. More than a third of men over age 45 may have reduced levels of testosterone than might be considered normal though, as mentioned, defining optimal levels of testosterone is tricky and somewhat controversial.
Some men who have a testosterone deficiency have symptoms or conditions related to their low testosterone that will improve when they take testosterone replacement. For example, a man with osteoporosis and low testosterone can increase bone strength and reduce his fracture risk with testosterone replacement. As surprising as it may be, women can also be bothered by symptoms of testosterone deficiency. For example, disease in the pituitary gland may lead to reduced testosterone production from the adrenal glands disease.
They may experience low libido, reduced bone strength, poor concentration or depression. There are times when low testosterone is textosterone such a bad thing. The most common example is probably prostate cancer. Testosterone may stimulate the prostate gland and prostate cancer to grow. That's why medications that lower testosterone levels for example, leuprolide and castration are common treatments for men with prostate cancer.
Men taking testosterone replacement must be carefully monitored for prostate cancer. Although testosterone may make how to create xslt stylesheet cancer grow, it is not clear that testosterone treatment actually causes cancer.
Genetic diseases, such as Klinefelter syndrome qnd which a man has an extra x-chromosome and hemochromatosis in which an abnormal gene causes excessive iron to accumulate throughout the whah, including the pituitary gland can also affect testosterone.
Women may have a testosterone deficiency due to diseases of the pituitary, hypothalamus or adrenal glands, in addition to removal of the ovaries. Estrogen therapy increases sex hormone binding globulin and, like aging men, this reduces the amount of free, active testosterone in the body. Currently, testosterone therapy is approved primarily for the treatment of delayed male puberty, low production of testosterone whether due to failure of the testes, pituitary or hypothalamus function and certain testostedone female breast cancers.
However, it is quite possible that testosterone treatment can improve symptoms in men with significantly low levels of active free testosterone, such as:. However, many men with normal testosterone levels have similar symptoms so a direct connection between testosterone levels and symptoms is not always clear.
As a result, there is some controversy about which men should be treated with supplemental testosterone. Testosterone therapy may make sense for women who have low testosterone levels and symptoms that might be due to testosterone deficiency. It's not clear if low levels without symptoms are meaningful; treatment risks may outweigh benefits. However, the wisdom and effectiveness of testosterone treatment to improve sexual function or cognitive function among postmenopausal women is unclear.
People with normal testosterone levels bory sometimes treated with testosterone at the recommendation of their doctors or they obtain the medication on their own. Some have recommended it as a "remedy" for aging. For example, a study teh Harvard Medical School in found that even among men who started out with normal testosterone results noted loss of fat, increased muscle mass, better mood, and less anxiety when receiving testosterone therapy.
Similar observations have been noted among women. However, the risks and side testosterine of taking testosterone when the body is already making enough still discourages widespread use. Testosterone is so much more than its reputation would suggest.
Men and women need the proper amount of testosterone to develop and function normally. However, the optimal amount of testosterone is far from clear. Checking testosterone levels is as easy as having a blood test. The difficult part is interpreting the result. Levels vary over the course of the day.
A single low level may be meaningless in the absence of symptoms, especially if it was normal at another ho. We need more wgat to know when to measure testosterone, how best to respond to the results and when it's worthwhile to accept the risks of treatment.
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Mar 05, · Male sex hormone testosterone is produced in a man’s testicles and has an effect on his behavior, brain, face, muscles and more. It is also produced in a woman’s ovaries, albeit in very small quantities, to help produce the female sex hormone, estrogen. Both low and high testosterone counts can result in a host of health issues.
More ». September 23, The complex effects of testosterone, investigators found, depend partly on its conversion in the body to a type of estrogen.
Testosterone is a sex hormone that plays important roles in the body. A small amount of circulating testosterone is converted to estradiol, a form of estrogen. As men age, they often make less testosterone, and so they produce less estradiol as well. Thus, changes often attributed to testosterone deficiency might be partly or entirely due to the accompanying decline in estradiol. Testosterone was first used as a clinical drug as early as , but with little understanding of its mechanisms.
The hormone is now widely prescribed to men whose bodies naturally produce low levels. A team led by Dr. Joel Finkelstein at Massachusetts General Hospital investigated testosterone and estradiol levels in healthy men, 20 to 50 years of age.
To control hormone levels, the researchers first gave the participants injections of a drug that suppressed their normal testosterone and estradiol production. Half of the participants were also given a drug to block testosterone from being converted to estradiol.
The participants were seen every 4 weeks. Blood was taken to measure hormone levels, and questionnaires were given to assess physical function, health status, vitality, and sexual function. Body fat and muscle measurements were also taken at the beginning and end of the 16 weeks. The researchers found that the dose of testosterone required to produce different effects in the body varied widely.
The influence of testosterone and estradiol also differed. As the testosterone gel dose was reduced, the scientists showed, reductions in lean mass, muscle size, and leg-press strength resulted from decreases in testosterone itself. In contrast, increases in body fat were due to the related declines in estradiol.
Both testosterone and estradiol levels were associated with libido and erectile function. The researchers are conducting follow-up clinical trials to address the effects of testosterone replacement both on the measures in this study and others, such as bone and prostate health. References: Gonadal steroids and body composition, strength, and sexual function in men. N Engl J Med. PMID: Site Menu Home.
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