Testosterone causes prostate cancer. Since the 1940s, it was commonly believed in the medical field that high testosterone levels were the cause of prostate cancer in men. Doctors reached this conclusion because two scientists in 1941 noticed that prostate cancer regressed in a patient after they castrated him and his T levels subsequently declined. This conclusion was based on the results from a single patient!

There is a negative correlation of testosterone levels with plasminogen activator inhibitor-1 (PAI-1) (Glueck et al 1993; Phillips 1993), which is a major prothrombotic factor and known to be associated with progression of atherosclerosis, as well as other prothrombotic factors fibrinogen, α2-antiplasmin and factor VII (Bonithon-Kopp et al 1988; Glueck et al 1993; Phillips 1993; De Pergola et al 1997). There is a positive correlation with tissue plasminogen activator (tPA) which is one of the major fibrinolytic agents (Glueck et al 1993). Interventional trials have shown a neutral effect of physiological testosterone replacement on the major clotting factors (Smith et al 2005) but supraphysiological androgen administration can produce a temporary mild pro-coagulant effect (Anderson et al 1995).
According to studies by Srivastava [15] and Thomson et al. [21] ginger can be used as natural antithrombotic agent. Ginger has also been recorded as useful remedy in preventing post-operative nausea and vomiting in humans [13] as well as preventing morning sickness during pregnancy [16]. At high doses (500 mg/kg) aqueous extract of ginger exhibits cholesterol-lowering effect [21].

Professional-athlete-turned-biohacker Maximilian Gotzler gave a speech about boosting testosterone at the 2015 Bulletproof Conference. He started by leading the room through the Haka, a Maori war dance that New Zealand’s pro rugby team has made popular. The Pasadena Conference Center trembled as over 100 people shouted and stomped in unison. It was awesome.
I have been on both pills and gel.While the pills were much more convenient, the gel seems to work better for me. I feel more focused and clear of mind with gel therapy. I’ve also noticed more sexual interest (closer to levels when younger – now 65) and get ‘harder’ when I do get an erection. The therapy has been good for me emotionally and physically. I’ll stay on it until and if negative signs/symptoms arise.
In the 2nd study, short-term testosterone treatment in older men significantly increased noncalcified coronary artery plaque volumes, possibly raising their risk of cardiovascular (CV) events,2 according to Matthew J. Budoff, MD, a professor of medicine at the David Geffen School of Medicine at UCLA and the Los Angeles Biomedical Research Institute in Torrance, California, and colleagues. 
As mentioned earlier, too much protein can negate testosterone production quite a bit. If your protein intake is over 0.85g/lb of body weight a day, then you may not be making full use of each of the nutrients. Consuming these high amounts of protein can cause your cortisol and SHBG levels to increase, which in turn lowers testosterone production. What do you get out of this deal? Increased fat gain and lower testosterone levels.
Testosterone is the main hormone associated with muscle mass, strength gains, and libido. But that's far from the only thing it does in the body. As Chris Lockwood, Ph.D., explains in the article "All About Testosterone," it impacts everything from mood and memory to bone health—but yes, to be clear, it also makes muscles bigger and stronger, and helps increase endurance and athletic performance.
Likewise, there are also natural ways to pep up your testosterone through diet, exercise and other lifestyle changes. So if you’re the wrong side of 30 and not feeling as strong in the gym anymore, or if you’re gaining weight where there wasn’t weight before, or if you can't find the energy to finish the day, let alone pleasure your partner, then keep reading — our expert advice may restore you to the peak of masculinity.
For example, in February 2017, scientists reported on trials involving men over age 65 who had low testosterone due to aging. Each trial included a different number of men depending on the subject of the research. Roughly half of the participants received testosterone therapy for a year; the rest underwent a placebo treatment. The researchers discovered the following:

I highly recommend using a great essential amino acid mix post-exercise in order to boost testosterone.  These essential amino acids and especially the concentrated branched chain amino acids leucine, isoleucine and valine stimulate muscle protein synthesis.  Getting these amino acids in the post-workout window dramatically boosts testosterone production (14).  I like using our Amino Strong and will often recommend a scoop pre-workout and post-workout for the best muscle building, testosterone boosting benefits.
If your priority is to find and use a safe, effective, and natural testosterone booster, then you have every right to ask yourself do all of these hormone supplements work for real? Also, do they work at all? Are you going to waste your money or finally find an answer to your burning questions? Well, long story short, the testosterone supplements do their work just fine.

I am sorry but if you are a doctor you really are making it obvious that it’s possible for doctors to know nothing about this problem.What kind of Doctor are you? Or did you get a doctorate in some obscure field? Are you a reverend doctor by chance? I think for the sake of people who need this help you should quit talking out your ass .I won’t say you are wrong.You have already proved you don’t know anything useful about HRT and I doubt you are a doctor.
The researchers found that men who received hormone treatment experienced an increase in bone strength and density. Strength increases were greater in the spine than they were in the hip. However, as with other T Trials, more research needs to be done. A larger study over many years would need to be performed to determine whether testosterone could decrease risk of bone fracture.
Consuming high amounts of sugary foods raises your blood glucose levels, which causes your body to release insulin as a response to the raised blood glucose levels. If not managed correctly, the body begins to develop a tolerance to insulin and cannot absorb the sugars in the blood stream as it used to, causing you to become insulin resistant. Being insulin resistant releases cortisol, and as you know, cortisol has extremely negative effects, lowering testosterone by quite a bit.
The mechanism of age related decreases in serum testosterone levels has also been the subject of investigation. Metabolic clearance declines with age but this effect is less pronounced than a reduction in testosterone production, so the overall effect is to reduce serum testosterone levels. Gonadotrophin levels rise during aging (Feldman et al 2002) and testicular secretory responses to recombinant human chorionic gonadotrophin (hCG) are reduced (Mulligan et al 1999, 2001). This implies that the reduced production may be caused by primary testicular failure but in fact these changes are not adequate to fully explain the fall in testosterone levels. There are changes in the lutenising hormone (LH) production which consist of decreased LH pulse frequency and amplitude, (Veldhuis et al 1992; Pincus et al 1997) although pituitary production of LH in response to pharmacological stimulation with exogenous GnRH analogues is preserved (Mulligan et al 1999). It therefore seems likely that there are changes in endogenous production of GnRH which underlie the changes in LH secretion and have a role in the age related decline in testosterone. Thus the decreases in testosterone levels with aging seem to reflect changes at all levels of the hypothalamic-pituitary-testicular axis. With advancing age there is also a reduction in androgen receptor concentration in some target tissues and this may contribute to the clinical syndrome of LOH (Ono et al 1988; Gallon et al 1989).
Using steroids eventually trains your body to realize that it doesn’t have to produce as much testosterone to reach its equilibrium, so to reach the same highs you’ll need to take more steroids, and when you stop taking them, your body will need to readjust — you’ll be living with low testosterone for a while (and you’ll need to see a doctor if your body doesn’t readjust on its own). Forcing your body to stay above your natural testosterone, even if you’re naturally low, can create this kind of dependency which ultimately decreases the amount of testosterone your body will produce on its own.
For years, the recommendation has been to get a testosterone value early in the morning because levels start to drop after 10 or 11 a.m. But the data behind that recommendation were drawn from healthy young men. Two recent studies showed little change in blood testosterone levels in men 40 and older over the course of the day. One reported no change in average testosterone until after 2 p.m. Between 2 and 6 p.m., it went down by 13%, a modest amount, and probably not enough to influence diagnosis. Most guidelines still say it’s important to do the test in the morning, but for men 40 and above, it probably doesn’t matter much, as long as they get their blood drawn before 5 or 6 p.m.

As with cognitive effects, previous studies examining CVD changes following testosterone treatment have been conflicting and inconclusive. Dr. Budoff and his research team used coronary computed tomographic angiography (CCTA) to assess 138 men, including 73 treated with testosterone and 65 receiving placebo, for changes in coronary artery plaque volume after 1 year.


There are three ways to increase testosterone activity naturally with simple lifestyle choices. The first is to increase total testosterone production. Second is to increase the amount of free and active testosterone that can stimulate testosterone receptors. The third is to unblock testosterone receptors, opening them up for testosterone stimulation.
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Travison, T. G., Vesper, H. W., Orwoll, E, Wu, F., Kaufman, J. M., Wang, Y., …Bhasin, S. (2017, April1). Harmonized reference ranges for circulating testosterone levels in men of four cohort studies in the United States and Europe. The Journal of Clinical Endocrinology & Metabolism, 102(4), 1161–1173. Retrieved from https://academic.oup.com/jcem/article/102/4/1161/2884621

An added testosterone benefit of my high fat and balanced protein and carb diet was that it probably helped me lose some body fat (I went from 18% to 12% body fat). Studies show that high fat diets actually contribute to increased body fat loss. And as we discussed earlier, as you lose body fat, your T production ramps up. Virtuous cycle for the win!

Ashwagandha: One of the hottest herbs out there right now, this adaptogen packs a one-two punch. First, it helps the body fight off stress: According to one Indian Journal of Psychological Medicine study, ashwagandha has a cortisol-lowering effect—a major benefit to anyone who wants their body to be more T-friendly. And, second, it can also support your T-boosting training efforts. One Journal of the International Society of Sports Nutrition study, for example, found that men who supplemented with ashwagandha saw significantly greater strength and T gains after eight weeks of resistance training than those who took a placebo.


Why bother with such common micronutrients? Because it's not uncommon for athletes to suffer from zinc and magnesium deficiencies, partly due to inadequate replenishing of levels after intense bouts of exercise. Deficiencies in these key minerals can lead to a poor anabolic hormone profile, impaired immune function, and increased cortisol, ultimately leading to decreases in strength and performance.[6]

The hypogonadal-obesity-adipocytokine cycle hypothesis. Adipose tissue contains the enzyme aromatase which metabolises testosterone to oestrogen. This results in reduced testosterone levels, which increase the action of lipoprotein lipase and increase fat mass, thus increasing aromatisation of testosterone and completing the cycle. Visceral fat also promotes lower testosterone levels by reducing pituitary LH pulse amplitude via leptin and/or other factors. In vitro studies have shown that leptin also inhibits testosterone production directly at the testes. Visceral adiposity could also provide the link between testosterone and insulin resistance (Jones 2007).


We should probably start with the elephant in the room: do these supplements increase testosterone? The answer is probably yes. There are some ingredients that help convince your body to produce more testosterone, but there’s a catch. Testosterone boosters aren’t actually great at boosting; that is, at pushing your testosterone levels above your healthy, normal balance. Boosters typically act more like restorers — helping bring low testosterone levels back to that healthy equilibrium rather than boosting you above normal testosterone levels. Just like how if you have anemia, taking a vitamin B12 supplement can help restore your energy and reduce fatigue, but if your B12 levels are good, a supplement won’t give you super energy levels to stay awake for three days — your body will likely just process (read: pee) out the extra.
Changes in body composition are seen with aging. In general terms, aging males are prone to loss of muscle mass and a gain in fat mass, especially in the form of visceral or central fat. An epidemiological study of community dwelling men aged between 24 and 85 years has confirmed that total and free testosterone levels are inversely correlated with waist circumference and that testosterone levels are specifically related to this measure of central obesity rather than general obesity (Svartberg, von Muhlen, Sundsfjord et al 2004). Prospective studies show that testosterone levels predict future development of central obesity (Khaw and Barrett-Connor 1992; Tsai et al 2000). Reductions in free testosterone also correlate with age related declines in fat free mass (muscle mass) and muscle strength (Baumgartner et al 1999; Roy et al 2002). Studies in hypogonadal men confirm an increase in fat mass and decrease in fat free mass versus comparable eugonadal men (Katznelson et al 1998). Taken together, the epidemiological data suggest that a hypogonadal state promotes loss of muscle mass and a gain in fat mass, particularly visceral fat and therefore mimics the changes of ‘normal’ aging.
A large number of side-effects have been attributed to testosterone. In our clinical experience, the incidence of significant adverse effects with treatment producing physiological testosterone levels is low, and many side effects attributed to testosterone are mainly relevant to supraphysiological replacement. Some adverse effects are specific to a given mode of delivery and have already been described. Potential adverse effects concerning the prostate have also been discussed and require appropriate monitoring of symptoms, PSA and digital rectal examination. Other tumors which may be androgen responsive include cancer of the breast and primary liver tumors, and these are both contraindications to testosterone treatment
While steroids like DHEA can be used to boost testosterone, if used in the wrong dosages or by people who don’t need them they can raise T-levels far beyond the normal range, which is what causes accelerated muscle gain. According to Dr. Emil Hodzovic, who is a competitive bodybuilder as well as a doctor with Medichecks, steroids come with “a set of risks, including liver damage, hormone imbalance, high blood pressure, and a higher risk of a stroke or heart attack”.

When you're under a lot of stress, your body releases high levels of the stress hormone cortisol. This hormone actually blocks the effects of testosterone,6 presumably because, from a biological standpoint, testosterone-associated behaviors (mating, competing, aggression) may have lowered your chances of survival in an emergency (hence, the "fight or flight" response is dominant, courtesy of cortisol).
The normal development of the prostate gland is dependent on the action of testosterone via the androgen receptor, and abnormal biosynthesis of the hormone or inactivating mutations of the androgen receptor are associated with a rudimentary prostate gland. Testosterone also requires conversion to dihydrotestosterone in the prostate gland for full activity. In view of this link between testosterone and prostate development, it is important to consider the impact that testosterone replacement may have on the prevalence and morbidity associated with benign prostatic hypertrophy (BPH) and prostate cancer, which are the common conditions related to pathological growth of the prostate gland.
I am 45 years old and have been diagnosed with low testosterone levels. In 2014 my levels were 16.5 and in 2016 that dramatically reduced to a score of 10.4. My doctor prescribed me Testo gel which I rub on every morning and have done so for the last 6 weeks. I keep myself fit, gym twice a week and martial arts twice a week and found my energy levels were depleting and didn’t seem to recover quickly the next day. I started to feel exhausted and experienced low libido,lack of motivation and mental focus. I actually thought oh well this is what happens when you get older.
“We need carbs, fats, and proteins to have optimal T levels,” says Howse. A healthy amount of carbs, for example, keeps cortisol levels low (more on why this is important to come). Meanwhile, dietary fats produce cholesterol, which our body can later convert into testosterone. And, finally, protein supports body composition by enhancing muscle repair and growth and increasing satiety.

Hello..was prescribe andro gel 1.62 for about 2 years..borderline low..At time 54 year old now 57..a year ago switched doctors..new doctor would not prescribe andro gel..without me stopping use and then being checked after 6 months..it’s been a year..by the way felt great while on it much more energy. .did notice some hair receding. .but felt stronger..my question is..by using andro gel ..did I turn off my body’s natural ability to make testosterone as using andro gel..if so what do I need to do too turn my body on if my doctor does not renew therapy. .by way the past without andro gel…little too no energy..weight gain of 40 lbs..especially around the belly..thank you for your time and reply

I was reading in the university health news daily website that a study performed by researchers at the University of Texas M.D. Anderson Cancer Center found that men with prostate cancer who ate 3 tablespoons of milled or ground flax seeds each day had decreased prostate cancer cell proliferation compared to similar men who did not eat flax seeds. According to the American Cancer Society, men who supplement their diets with flax seed have lower PSA levels and slower growth of benign as well as cancerous prostate cells.


To date, no large, double-blind, randomized controlled studies of a link between testosterone treatment and prostate cancer have been completed. In its 2004 report, the Institute of Medicine (IOM) committee studying the need for clinical trials of testosterone-replacement therapy noted that only 31 placebo-controlled studies had been done in older men, with the largest one enrolling just 108 participants. Most of these studies lasted only six months.
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Whether you are currently on a plateau or you are looking to obtain more energy in life and in the gym this test booster and its full coverage blend of natural extracts is designed to support your body’s anabolic potential without compromising natural production. Test Booster 1.0 works with your body to promote elevations in natural test levels; helping to support muscle density, a balanced metabolism, and insane natural energy levels.
Testosterone may prove to be an effective treatment in female sexual arousal disorders,[52] and is available as a dermal patch. There is no FDA approved androgen preparation for the treatment of androgen insufficiency; however, it has been used off-label to treat low libido and sexual dysfunction in older women. Testosterone may be a treatment for postmenopausal women as long as they are effectively estrogenized.[52]
Trials of testosterone treatment in men with type 2 diabetes have also taken place. A recent randomized controlled crossover trial assessed the effects of intramuscular testosterone replacement to achieve levels within the physiological range, compared with placebo injections in 24 men with diabetes, hypogonadism and a mean age of 64 years (Kapoor et al 2006). Ten of these men were insulin treated. Testosterone treatment led to a significant reduction in glycated hemoglobin (HbA1C) and fasting glucose compared to placebo. Testosterone also produced a significant reduction in insulin resistance, measured by the homeostatic model assessment (HOMA), in the fourteen non-insulin treated patients. It is not possible to measure insulin resistance in patients treated with insulin but five out of ten of these patients had a reduction of insulin dose during the study. Other significant changes during testosterone treatment in this trial were reduced total cholesterol, waist circumference and waist-hip ratio. Similarly, a placebo-controlled but non-blinded trial in 24 men with visceral obesity, diabetes, hypogonadism and mean age 57 years found that three months of oral testosterone treatment led to significant reductions in HbA1C, fasting glucose, post-prandial glucose, weight, fat mass and waist-hip ratio (Boyanov et al 2003). In contrast, an uncontrolled study of 150 mg intramuscular testosterone given to 10 patients, average age 64 years, with diabetes and hypogonadism found no significant change in diabetes control, fasting glucose or insulin levels (Corrales et al 2004). Another uncontrolled study showed no beneficial effect of testosterone treatment on insulin resistance, measured by HOMA and ‘minimal model’ of area under acute insulin response curves, in 11 patients with type 2 diabetes aged between 33 and 73 years (Lee et al 2005). Body mass index was within the normal range in this population and there was no change in waist-hip ratio or weight during testosterone treatment. Baseline testosterone levels were in the low-normal range and patients received a relatively small dose of 100 mg intramuscular testosterone every three weeks. A good increase in testosterone levels during the trial is described but it is not stated at which time during the three week cycle the testosterone levels were tested, so the lack of response could reflect an insufficient overall testosterone dose in the trial period.
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Some foods, vitamins, and herbs can help boost your testosterone levels. Be sure to talk to your doctor, if you’re concerned about low testosterone. These alternative and natural treatments aren’t proven to be more, or as, effective as traditional testosterone therapy. Some may also interact with any medications you may be taking and cause unintended side effects.
“She” being the key word. I had to quit a female doc because even though my level was down to 200, she thought I just needed more vitamin D! When I tried that and came back a few weeks later and told her there was no change in how I felt she refused to order another blood test, and after that wouldn’t even see me. I would never trust a female doctor with testosterone replacement therapy, as they all seem to have the same shit attitude from what my friends have told me, they treat it like it’s not a real thing even though you better bow down and kiss their asses when it comes to breast cancer and menopause.
Testosterone is the primary male sex hormone and an anabolic steroid. In male humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair.[2] In addition, testosterone is involved in health and well-being,[3] and the prevention of osteoporosis.[4] Insufficient levels of testosterone in men may lead to abnormalities including frailty and bone loss.
Like most supplements, Beast Sports contains several ingredients with little research about their long-term effects. WebMD describes Suma powder, Rhodiola Rosea, Cissus quadrangularis, Tribulus extract, and ashwagandha extract as possibly safe when taken for a short period of time (usually around 6-10 weeks). However, their long-term safety remains unknown. It also has a few ingredients, like cyanotis vaga root, safed musli, and polygonum cispidatum root extract for which there is a lack of data on even short term safety.

If your levels are indeed low, there are a number of synthetic and bioidentical testosterone products on the market, as well as DHEA, which is the most abundant androgen precursor prohormone in the human body, meaning that it is the largest raw material your body uses to produce other vital hormones, including testosterone in men and estrogen in women.
Most Americans today are sleep deprived, which may be a contributing factor to declining testosterone levels in men. See, our body makes nearly all the testosterone it needs for the day while we’re sleeping. That increased level of T that we experience at night is one of the reasons we wake up with “Morning Wood.” (If you don’t have Morning Wood on a consistent basis, you might have low T).
Some of them can benefit dieters or competitive athletes. These individuals often experience significant decreases in their testosterone levels as a result of the restrictive or stressful exercise or diet regimen. It is worth mentioning that many of them can actually benefit healthy and hyper-active individuals (for example, professional weight lifters), but we can’t know that for sure because there aren’t enough studies to back up this claim.

My biggest symptom was fatigue. Interestingly, I had and have no problem with erections at all. Granted, I wasn’t getting spontaneous erections like when I was a teenager and into my late 20’s, but that was a good thing as getting an erection whenever and having no way to relieve it can get annoying. Anyway, my biggest concern with low T was/is energy levels and loss of muscle mass.
It seems like today it’s a badge of honor to train every day until exhaustion. The ethos is to push yourself harder and harder every day. If that’s your philosophy towards exercise, you might be sabotaging your testosterone levels (as well as your 20 Mile March). Studies have shown that overtraining can reduce testosterone levels significantly. Yes, it’s important to exercise hard, but it’s even more important to give your body rest so it can recuperate from the damage you inflicted upon it.

A4M, which stands for “The American Academy of Anti-Aging Medicine” is dedicated to the advancement of tools, technology, and transformations in healthcare that can detect, treat, and prevent diseases associated with aging. They promote the research of practices and protocols that have the potential to optimize the human aging process. The organization is also dedicated to educating healthcare professionals and practitioners, scientists, and members of the public on biomedical sciences, breakthrough technologies, and medical protocols through our advanced education entity: Metabolic Medical Institute (MMI). Their event in Vegas each year is, in my opinion, well worth checking out.
Testosterone makes you angry. This is probably the most common myth about T. The reality is that there’s no concrete evidence that high testosterone levels cause anger and violent outbursts. In fact, the opposite might be true; low testosterone, not high T, is what causes anger and irritability in men. As discussed above, having low T levels has been linked to depression in men and it just so happens that two of the primary symptoms of depression in men are increased angry outbursts and irritability. So if you’re chronically angry, you might be depressed, and you might be depressed because you have low T. As I mentioned above, I became less moody and irritable during my experiment, which I attribute to the boost in my testosterone levels.

14. Volek JS, Volk BM, Gómez AL, Kunces LJ, Kupchak BR, Freidenreich DJ, Aristizabal JC, Saenz C, Dunn-Lewis C, Ballard KD, Quann EE, Kawiecki DL, Flanagan SD, Comstock BA, Fragala MS, Earp JE, Fernandez ML, Bruno RS, Ptolemy AS, Kellogg MD, Maresh CM, Kraemer WJ. Whey protein supplementation during resistance training augments lean body mass. J Am Coll Nutr. 2013;32(2):122-35. PMID: 24015719
A large number of trials have demonstrated a positive effect of testosterone treatment on bone mineral density (Katznelson et al 1996; Behre et al 1997; Leifke et al 1998; Snyder et al 2000; Zacharin et al 2003; Wang, Cunningham et al 2004; Aminorroaya et al 2005; Benito et al 2005) and bone architecture (Benito et al 2005). These effects are often more impressive in longer trials, which have shown that adequate replacement will lead to near normal bone density but that the full effects may take two years or more (Snyder et al 2000; Wang, Cunningham et al 2004; Aminorroaya et al 2005). Three randomized placebo-controlled trials of testosterone treatment in aging males have been conducted (Snyder et al 1999; Kenny et al 2001; Amory et al 2004). One of these studies concerned men with a mean age of 71 years with two serum testosterone levels less than 12.1nmol/l. After 36 months of intramuscular testosterone treatment or placebo, there were significant increases in vertebral and hip bone mineral density. In this study, there was also a significant decrease in the bone resorption marker urinary deoxypyridinoline with testosterone treatment (Amory et al 2004). The second study contained men with low bioavailable testosterone levels and an average age of 76 years. Testosterone treatment in the form of transdermal patches was given for 1 year. During this trial there was a significant preservation of hip bone mineral density with testosterone treatment but testosterone had no effect on bone mineral density at other sites including the vertebrae. There were no significant alterations in bone turnover markers during testosterone treatment (Kenny et al 2001). The remaining study contained men of average age 73 years. Men were eligible for the study if their serum total testosterone levels were less than 16.5 nmol/L, meaning that the study contained men who would usually be considered eugonadal. The beneficial effects of testosterone on bone density were confined to the men who had lower serum testosterone levels at baseline and were seen only in the vertebrae. There were no significant changes in bone turnover markers. Testosterone in the trial was given via scrotal patches for a 36 month duration (Snyder et al 1999). A recent meta-analysis of the effects on bone density of testosterone treatment in men included data from these studies and two other randomized controlled trials. The findings were that testosterone produces a significant increase of 2.7% in the bone mineral density at the lumber spine but no overall change at the hip (Isidori et al 2005). These results from randomized controlled trials in aging men show much smaller benefits of testosterone treatment on bone density than have been seen in other trials. This could be due to the trials including patients who are not hypogonadal and being too short to allow for the maximal effects of testosterone. The meta-analysis also assessed the data concerning changes of bone formation and resorption markers during testosterone treatment. There was a significant decrease in bone resorption markers but no change in markers of bone formation suggesting that reduction of bone resorption may be the primary mode of action of testosterone in improving bone density (Isidori et al 2005).
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