The unsexy truth is that increasing T naturally simply comes down to making some long-term changes in your diet and lifestyle. As you’ll see, what I did to increase T largely boils down to eating better, exercising smarter, and getting more sleep. That’s pretty much it. But as with most things in life, the devil is in the details, so I’ll share with you exactly what I did and provide research that explains why the things I did helped boost my testosterone.
There’s a significant failure rate of the PDE5 inhibitors for erectile dysfunction, something on the order of 25% to 50%, depending on the underlying condition. It turns out that a third of those men will have adequate erections with testosterone-replacement therapy alone and another third will have adequate erections with the pills and testosterone combined. There’s still a third who don’t respond, but normalizing their testosterone level has definitely rescued many men who had failed on PDE5 inhibitors.
Inaccurate or misinterpreted test results can either falsely diagnose or miss a case of testosterone deficiency. Your testosterone level should be measured between 7 am and 10 am, when it's at its peak. Confirm a low reading with a second test on a different day. It may require multiple measurements and careful interpretation to establish bioavailable testosterone, or the amount of the hormone that is able to have effects on the body. Consider getting a second opinion from an endocrinologist.
The effects of testosterone in humans and other vertebrates occur by way of multiple mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors.[113][114] Androgens such as testosterone have also been found to bind to and activate membrane androgen receptors.[115][116][117]
Men on long-term testosterone appear to have a higher risk of cardiovascular problems, like heart attacks, strokes, and deaths from heart disease. For example, in 2010, researchers halted the Testosterone in Older Men study when early results showed that men on hormone treatments had noticeably more heart problems. "In older men, theoretical cardiac side effects become a little more immediate," Dr. Pallais says.

An international consensus document was recently published and provides guidance on the diagnosis, treatment and monitoring of late-onset hypogonadism (LOH) in men. The diagnosis of LOH requires biochemical and clinical components. Controversy in defining the clinical syndrome continues due to the high prevalence of hypogonadal symptoms in the aging male population and the non-specific nature of these symptoms. Further controversy surrounds setting a lower limit of normal testosterone, the limitations of the commonly available total testosterone result in assessing some patients and the unavailability of reliable measures of bioavailable or free testosterone for general clinical use. As with any clinical intervention testosterone treatment should be judged on a balance of risk versus benefit. The traditional benefits of testosterone on sexual function, mood, strength and quality of life remain the primary goals of treatment but possible beneficial effects on other parameters such as bone density, obesity, insulin resistance and angina are emerging and will be reviewed. Potential concerns regarding the effects of testosterone on prostate disease, aggression and polycythaemia will also be addressed. The options available for treatment have increased in recent years with the availability of a number of testosterone preparations which can reliably produce physiological serum concentrations.


I am 50 yrs old. I tried to go the route my urologist provide of 50mgs of injectable test weekly. No man can live on that dose. For the past five years I have self administered injectable cyponate at the rate of 250 mgs to 750 mgs weekly. Non stop , no breaks. I have polycythemia from these injections. I give blood every 8 weeks to combat this. I have administered 10 X the recommended dose with no bad side effects. I get full blood work done yearly. Doctors are so scared they will get sued if something happens that they wont give you enough. Its a shame.
I’m afraid I have no super cool “secrets” to share and there are no easy shortcuts to increasing your T. If you were expecting some magical potion or supplement or weird body hack that will instantly and naturally increase your T levels, what follows is bound to disappoint. Despite what some companies or websites might tell you, there’s no single thing that will boost your testosterone naturally for the long term.
12. We keep you informed with a FREE eNewsletter – a $19.95 value. Every month, we send a short science-backed newsletter updating you on the latest research on Testosterone and your health. In addition, we email once-a-week “T-Tips” which are brief, to-the-point tips to help you see better results. This is a $19.95 value absolutely FREE to our customers!
The doctor regularly measured my levels to be sure they were within the normal range for a male my age. In other words, I wasn’t taking ‘roids to get big; I was getting control of hormones that were not functioning well. This is how you should look at testosterone therapy – it is a gentle nudge to help you be in normal ranges, not a big push to get you huuu-yge. If you’re like me, you want “normal ranges” of a 27-year-old, not of a 60-year-old. It’s my plan to keep my testosterone where it is now (around 700) no matter what it takes. Right now, the Bulletproof Diet and the other biohacks I’ve written about do that! I’m 43.
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“I have seen them work for people,” says GP and hormonal therapy expert at Omniya London, Dr Sohere Roked. “I think sometimes people feel that it’s not a good thing to do or they’re just wasting their time taking it, but I have seen people who combine that with a good diet and exercise and have noticed a change in their physique, their energy, their mood, and the sort of things that testosterone would naturally help.”


A recent study conducted on trained subjects showed that squats stimulated a greater testosterone response than leg presses.10 Stick with multijoint exercises like squats, bench presses, and deadlifts—the kinds of compound lifts that'll help jack up your testosterone levels. Since machines isolate a muscle you're working (less stabilizer activity), they're not as good a choice compared to free weights.
Side note, insurance rarely will cover it and cause a long paper trail to even approve it which is unfortunate and disheartening. Especially when it is done out of network. Currently I have found a place to supply all of the aboue sent to my house at approximately $200.00 per month. Still an unfortunate cost for a medical reason that the insurance companies don’t approve. Best of luck to all of you.
Topical testosterone, specifically gels, creams and liquids, may transfer to others. Women and children are most at risk of harmful effects from contact with them. You should take care to cover the area and wash your hands well after putting on the medication. Be careful not to let the site with the topical TT touch others because that could transfer the drug.
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.
Falling in love decreases men's testosterone levels while increasing women's testosterone levels. There has been speculation that these changes in testosterone result in the temporary reduction of differences in behavior between the sexes.[53] However, it is suggested that after the "honeymoon phase" ends—about four years into a relationship—this change in testosterone levels is no longer apparent.[53] Men who produce less testosterone are more likely to be in a relationship[54] or married,[55] and men who produce more testosterone are more likely to divorce;[55] however, causality cannot be determined in this correlation. Marriage or commitment could cause a decrease in testosterone levels.[56] Single men who have not had relationship experience have lower testosterone levels than single men with experience. It is suggested that these single men with prior experience are in a more competitive state than their non-experienced counterparts.[57] Married men who engage in bond-maintenance activities such as spending the day with their spouse/and or child have no different testosterone levels compared to times when they do not engage in such activities. Collectively, these results suggest that the presence of competitive activities rather than bond-maintenance activities are more relevant to changes in testosterone levels.[58]
The use of these supplements can help to burn fat and build muscles. As a result, the health and strength of your muscles and bones improve that ultimately leads to a strong and healthy body. Another prominent feature of Testosterone Booster is that it can help to elevate mood and energy. These supplements contains a powerful blend of natural herbs. These natural herbs have healthful properties. Thus, you can have the energy and stamina to perform your best in the gym. Furthermore, these supplements will also help you to increase your productivity at work because of your improved energy levels.

Fenugreek, in the form of a capsule, testofen, or Fenugreek tea could do the trick. The fact that fenugreek increases libido is not mythology; it is backed by a clinical study which showed the libido of men aged 25-52 increased by 25%[1] on average when taking fenugreek extract for six weeks.  According to Lee Myer, of www.peaktestosterone.com fame, fenugreek will help you achieve orgasm as well, so if this is an issue for you, fenugreek may be the answer.  It’s a frustrating problem to have.

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.


I think that the biggest hurdle for most physicians prescribing testosterone is the fear that they’re going to promote prostate cancer. [See “Incongruous findings,” below.] That’s because more than six decades ago, it was shown that if you lowered testosterone in men whose prostate cancer had metastasized, their condition improved. (It became a standard therapy that we still use today for men with advanced prostate cancer. We call it androgen deprivation or androgen-suppressive therapy.) The thinking became that if lowering testosterone makes prostate cancer disappear, at least for a while, then raising it must make prostate cancer grow. But even though it’s been a widely held belief for six decades, no one has found any additional evidence to support the theory.

Testosterone was first used as a clinical drug as early as 1937, but with little understanding of its mechanisms. The hormone is now widely prescribed to men whose bodies naturally produce low levels. But the levels at which testosterone deficiency become medically relevant still aren’t well understood. Normal testosterone production varies widely in men, so it’s difficult to know what levels have medical significance. The hormone’s mechanisms of action are also unclear.

TestoRush is a decent natural testosterone booster with decent ingredients. It’s not nearly as potent as some other higher ranked supplements on this site, and, in reading every review we could find from customers, it appears there’s some negativity towards the company. Read this full TestoRush review and find out how it measures up to other boosters we’ve reviewed. READ THE REVIEW

A: According to the package insert, there are several longer-term side effects that have occurred with testosterone therapy. Testosterone can stimulate the growth of cancerous tissue. Prostate cancer or enlargement of the prostate can develop during prolonged therapy with testosterone, and these conditions are more likely to occur in elderly men. In patients receiving testosterone therapy, tests for prostate cancer should be performed as is current practice. Androgen therapy, such as testosterone, can cause a loss of blood sugar control in patients with diabetes. Close monitoring of blood glucose is recommended. Male patients can experience feminization during prolonged therapy with testosterone. The side effects of feminization include breast soreness and enlargement. These side effects are generally reversible when treatment is stopped. Hair loss resembling male pattern baldness has also occurred. Sexual side effects including decreased ejaculatory volume and low sperm counts have occurred in patients receiving long-term therapy or excessive doses. For more information, please consult with your health care provider and visit //www.everydayhealth.com/drugs/testosterone. Michelle McDermott, PharmD


It doesn’t get more natural than getting a good night’s sleep. Research published in the Journal of the American Medical Association showed that lack of sleep can greatly reduce a healthy young man’s testosterone levels. That effect is clear after only one week of reduced sleep. Testosterone levels were particularly low between 2 and 10 p.m. on sleep-restricted days. Study participants also reported a decreased sense of wellbeing as their blood testosterone levels dropped.
Longjack, also known as Tongkat ali and pasak bumi, is a shrub hailing from Southeast Asia purporting to improve libido. It’s gaining traction in the scientific community for potentially increasing testosterone levels, and researchers at South Africa’s University of the Western Cape found that longjack improved testosterone levels and muscular strength in physically active seniors (a population with typically low testosterone).
^ Jump up to: a b Sapienza P, Zingales L, Maestripieri D (September 2009). "Gender differences in financial risk aversion and career choices are affected by testosterone". Proceedings of the National Academy of Sciences of the United States of America. 106 (36): 15268–73. Bibcode:2009PNAS..10615268S. doi:10.1073/pnas.0907352106. PMC 2741240. PMID 19706398.
Sergeant Steel ran into trouble here because it contains Shilajit — a type of plant-based resin. Shilajit is banned in Canada because the Canadian government found heavy metal levels when investigating the ingredient. Shilajit is hard to find, and sensitive to water and variations in temperature, so most manufacturers mix it with additives to make it more stable. Research at Boston University School of Medicine found that “nearly 21 percent of 193 ayurvedic herbal supplements [...] contained lead, mercury or arsenic,” and included shilajit on the list of contaminated ingredients. Even though Sergeant Steel lists its shilajit is “purified,” it doesn’t offer any third-party testing to confirm whether or not their shilajit contains heavy metals, and so we cut it.
Magnesium: About 60% of our (if you’re a man) testosterone is bound to Sex Hormone Binding Globulin (SHBG), which removes the anabolism of testosterone and the availability thereof, robbing the rest of the body from any testosterone. What magnesium does is it lowers the SHBG count by quite a bit, granting the free testosterone in the body to increase in a large amount.
Let’s first start off by saying, there is no comparison of natural testosterone boosters to synthetic.  When referring to synthetic, we’re talking anabolic steroids.  At that point, you’re comparing apples and oranges.  Which is best—natural or synthetic?  Synthetic.  It is much easier to put on quality muscle mass while using anabolics than it is using a natural testosterone booster.  One is basically giving you synthetic testosterone while the other is giving you a minor boost in natural testosterone production.  However, not only are there side effects to the use of anabolics, but they are also illegal in the United States unless used under a doctor’s supervision with a prescription.

Vitamin D3 has the ability to naturally boost testosterone levels.  Increasing serum vitamin D levels in the body can help increase testosterone production, allowing you to potentially build muscle at a faster rate. If you don’t live in an area of the world that allows for a good amount of sunlight, you could become deficient and could benefit from a vitamin D supplement.
All information presented by TheSupplementReviews.org is for educational purposes only. In case of medical questions or uncertainties, the reader is encouraged to seek the advice of his/her own physician or health care practitioner. These statements have not been evaluated by the Food and Drug Administration. These products or any information contained within this site are not intended to diagnose, treat, cure or prevent any disease.
Beast Sports Nutrition - Super Test has all four of our dream ingredients: magnesium, fenugreek, longjack, and zinc. These ingredients have all been demonstrated to help increase natural testosterone levels, with plenty of scientific research to support them (done on humans too, and not just rats). By combining all four ingredients, Super Test has the best chance of helping to increase your testosterone levels, and thereby helping you gain muscle or have a more active sex life.
61y/o with 18month progressive lethargy, depressed mood, no sex drive, no erections. Doc put me on cymbalta (slept even more than 14hrs daily) then on Wellbutrin. All the time I was pushing for T testing. Came back low in March of this year and put on IM cypionate 100mg q3 weeks. Even I knew that was too low and infrequent. Nonetheless, that how it’s been since April. Finally got urology consult in Shreveport and got a level done at that time. Was 127 just two weeks after last injection. He is going to bump me up to 300mg q2 weeks and do a level 2 days after first injection and 1 day before next shot. Since I’m getting care thru VA, it’s a waiting game. Saw urologist last week. Prob won’t see testostosterone in mail for another week or two. I’m excited to feel like living again, not sleeping all the time, and perhaps some nooky now and then . Appreciated this article arm subsequent posts and personal trials. Would love to find a competent and assertive urologist in my area of Louisiana. I’m around Monroe….so if you know one, let me know!
Studies conducted in rats have indicated that their degree of sexual arousal is sensitive to reductions in testosterone. When testosterone-deprived rats were given medium levels of testosterone, their sexual behaviors (copulation, partner preference, etc.) resumed, but not when given low amounts of the same hormone. Therefore, these mammals may provide a model for studying clinical populations among humans suffering from sexual arousal deficits such as hypoactive sexual desire disorder.[37]

One study showed that six months of zinc supplementation among slightly zinc-deficient elderly men doubled serum levels of testosterone. And another eight-week trial found that college football players who took a nightly zinc supplement showed increased T-levels and increased leg strength that was 250 percent greater than a placebo! Holy quads, Batman! Research has also shown deficiencies in zinc to be a risk factor for infertility caused by low testosterone levels.

But can testosterone replacement therapy help with heart disease? Study results are mixed. Small studies in the early 2000s found that men with heart disease who underwent testosterone therapy saw only slight improvements. Some were able to increase their walking distance by 33 percent. Another study found that hormone therapy only widened healthy arteries but had no effect on angina pain.

Mínguez-Alarcón, L., Chavarro, J. E., Mendiola, J., Roca, M., Tanrikut, C., Vioque, J., ... Torres-Cantero, A. M. (2017, March–April). Fatty acid intake in relation to reproductive hormones and testicular volume among young healthy men [Abstract]. Asian Journal of Andrology, 19(2), 184–190. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/27834316
I thought your article was informative if researching effects of testosterone on cardiovascular and urological findings. However, it failed to key in on the psychological effects which cause noted behavioral changes. My husband was diagnosed with mildly low testosterone level and a fatty liver. Upon convincing his NP to put him on the topical gel as a first course of treatment he has stated he feels great, no longer foggy, and energetic like never before. Please understand, he was not having any sexual dysfunction but instead decreased energy and increased fatigue. What I also noticed is that he is now acting more dominant and agressive in his behavior. He speaks with the intent that nothing he says matters to him regardless of bluntness or disrespect. He has requested a divorce after 18 years of marriage without any prior indication that this was his intentions blindsiding our entire family and friend network. He recently got a job promotion since being on testosterone therapy and has a grandiose personal about him. He has lost 22 pounds and has decreased communications and contact with loved ones. He is scheduled to return to practitioner for a refill on his gel prescription and we, his family, are hoping that he may be taken off this medication which has drastically changed the man I have known for nearly 20 years. Unfortunately because he is a pilot and travels frequently we can only hope that he has not allowed his mental alertness spill over into his physical needs and allowed for infidelity to occur as he has changed all personal passwords, eliminated me accesss to flight benefits and checking account. We no longer get his schedule and therefore only await his sporadic call/texts to let us know if his whereabouts. He has developed a despiteful attitude towards me in a matter of 3 weeks which weeks. He has been on this medication for almost one month now. Prior to the medication, all was well and happy. This medication has completely changed our lives in a negative way. Perhaps practitioner need to consider the behavioral outcomes as well especially in men in their 40’s who may also be going through a mid life crisis. Take it from my firsthand experience that it is not been considered thoroughly in his case.
Since 2004, Andro400 has been the leader among natural testosterone boosters with a proven track record of successfully helping tens of thousands of customers increase their testosterone safely without side effects. Andro400 contains only the most highly researched and time-tested ingredients proven to naturally increase T levels. Enjoyed by men (and women) of all ages and results are backed by the industry's leading Satisfaction Guarantee.

High intensity exercise is crucial to boost testosterone (13).  Exercises should be explosive in nature and maximize the resistant overload on the muscles.  Large muscle group compound lifts such as squats, deadlifts & burpees are some of the best testosterone boosting exercises.  The training session should be short (5-30 mins) and have very little rest periods between sets.
What makes TestoFuel different from other testosterone boosters on the market is that the company is constantly researching and updating the ingredients. So, you know you are getting a product that has been formulated using the latest clinical studies. Unlike most other companies that formulate a product and update it every 3 – 5 years or never at all.

A recent study compared total and bioavailable testosterone levels with inflammatory cytokines in men aged 65 and over. There was an inverse correlation with the pro-inflammatory soluble interleukin-6 receptor, but no association with interleukin-6 (IL-6), highly sensitive CRP (hsCRP), tumor necrosis factor-α (TNF-α) or interleukin-1β (IL-1β (Maggio et al 2006). Another trial found that young men with idiopathic hypogonadotrophic hypogonadism had higher levels of proinflammatory factors interleukin-2 (IL-2), interleukin-4 (IL-4), complement C3c and total immunoglobulin in comparison to controls (Yesilova et al 2000). Testosterone treatment in a group of hypogonadal men, mostly with known coronary artery disease, induced anti-inflammatory changes in the cytokine profile of reduced IL-1β and TNF-α and increased IL-10 (Malkin, Pugh, Jones et al 2004).


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).
I have a large potion of my bowel removed resilting in me not digesting properly and shitting uncontrollably and an immovable staphs infection in my nose (due to pharmaceuticals) to deal with now, which as you can imagine inhibits me. Its these two last problems I’m looking to over come. I think this info in this article will help me a lot and so i want to say thanks to you (long winded i know) and see if you have ny other ideas for me to try.
A: Depo-Testosterone is a brand name medication that contains testosterone cypionate. Depo-Testosterone is given as an intramuscular injection. The medication is indicated for replacement therapy for men that have conditions associated with symptoms of deficiency in the hormone or absence of testosterone produced in the body. Conditions that can be associated with low testosterone include: delayed puberty, impotence and hormonal imbalances. Testosterone is a sex hormone that is naturally produced in the male testicles. In women, small amounts of testosterone is produced in the ovaries and by the adrenal system. Testosterone is available in various medications for testosterone replacement therapy. Different forms of testosterone (e.g. cypionate, enanthate etc) are contained in different brand name medications. Jen Marsico, RPh

The other interesting thing about the study: men’s testosterone levels were lowest in March (at the end of winter) and highest in August (at the end of summer). Sunlight affects your vitamin D production, so you have seasonal dips and peaks. Get a blood test to check your levels, and if you’re low, take a high-quality vitamin D3 supplement. If you’re going to take D3, take vitamin K2 and vitamin A with it. The three work in sync, so you want them all to be balanced. Here are my dosage recommendations.
Testosterone booster products obtained from trusted sources and administered as per the recommendations of the manufacturer may still present some health risks. The present case provided weak evidence of causality between acute liver injury and a commercial testosterone booster. To guarantee an optimal outcome with no severe side effects, further research is warranted to confirm the present findings and determine whether the effects observed in this case report would be statistically significant in larger samples.
The partial synthesis in the 1930s of abundant, potent testosterone esters permitted the characterization of the hormone's effects, so that Kochakian and Murlin (1936) were able to show that testosterone raised nitrogen retention (a mechanism central to anabolism) in the dog, after which Allan Kenyon's group[190] was able to demonstrate both anabolic and androgenic effects of testosterone propionate in eunuchoidal men, boys, and women. The period of the early 1930s to the 1950s has been called "The Golden Age of Steroid Chemistry",[191] and work during this period progressed quickly. Research in this golden age proved that this newly synthesized compound—testosterone—or rather family of compounds (for many derivatives were developed from 1940 to 1960), was a potent multiplier of muscle, strength, and well-being.[192]
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.

My favorite overall tool to manage stress is EFT (Emotional Freedom Technique), which is like acupuncture without the needles. It's a handy, free tool for unloading emotional baggage quickly and painlessly, and so easy that even children can learn it. Other common stress-reduction tools with a high success rate include prayer, meditation, laughter and yoga, for example. Learning relaxation skills, such as deep breathing and positive visualization, which is the "language" of the subconscious.
If you do take DAA I recommend cycling it (i.e. 5 days on, 2 off, over 4 weeks then 4 weeks off). And taking it with an aromatase inhibitor (which ensures the aspartic acid doesn’t get converted to estrogen). Especially as more studies are coming out showing the increase in testosterone is limited to a week or two before it drops back to normal levels.
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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