Grape seed extract is another ingredient with not enough research to suggest a dosage. Grape seed extract can interact with drugs like “blood thinners, NSAID painkillers (like aspirin, Advil, and Aleve), certain heart medicines, cancer treatments, and others.” If this sounds like you (or if you ever pop an Advil to clear off a headache), you’ll need to speak with a doctor to make sure this supplement is safe to take.
The Organon group in the Netherlands were the first to isolate the hormone, identified in a May 1935 paper "On Crystalline Male Hormone from Testicles (Testosterone)".[184] They named the hormone testosterone, from the stems of testicle and sterol, and the suffix of ketone. The structure was worked out by Schering's Adolf Butenandt, at the Chemisches Institut of Technical University in Gdańsk.[185][186]
I know many of you are clamoring for the “how-to” part of this series (which will go up on Thursday), but before we get to that, it’s important to cover why you should even care about your testosterone levels in the first place, what T is and how it’s made, and how to get properly tested for it. Building a sound foundation before we dive into the nitty gritty details will be highly beneficial.
Meat. Meat, particularly beef, provides our bodies with the protein it needs to create muscle (more muscle = more T) and the fats and cholesterol to make testosterone. My meat topping of choice was sliced up chuck steak. I grilled two of them on Monday and it lasted me until the next Monday. Every now and then I’d slow-cook some ribs or brisket to use as my meat topping. My philosophy was the fattier, the better.
The steroid hormone known as dehydroepiandrosterone, DHEA, plays an important role in sexual behavior, mental health and muscle growth. Your body uses this hormone to make sex steroids. Thus, taking a DHEA supplement should increase your circulating testosterone. A 2018 paper in the International Journal of Sports Medicine explored this possibility in athletic women.
In many of the studies we found, those who saw the most improvement in health, testosterone, or muscle gain were those with existing nutrient or vitamin deficiencies. This means that some gains may be due more to dietary changes and generally restoring nutrient and vitamin levels than any one magic ingredient, but also that making sure your diet includes healthy amounts of nutrients should be your first step.
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.
“I'm a truck driver and for 13 hours a night I sit in my truck and I drive. Out of boredom, I'd stop and eat. That was all until Andro400 – ever since then my life has changed. I started out weighing 341 pounds, and since taking Andro400 I've dropped 85 pounds! There's no cravings – I actually don't even think about food anymore. One thing that Andro400 said on the radio ad is it attacks belly fat – well let me tell you it did – the 2nd month is where I saw a drastic change in the size of my stomach. I've lost 6 inches! I'm sleeping better. My knee pain went away. I've had some lower back issues and that went away, and I can only attribute that to Andro400. It's a Life Changer for me!”
When I was on 4 pumps per day, I had a reduction of ejaculate, and sometimes found it hard to ejaculate. Getting erections is no problem, and I even take BP meds. I vary it now. When I’m not going to the gym, or traveling, I cut down to 2 pumps, or take a break for a few days. When I’m intense in the gym, I stick with 4 pumps (about 5mg). I do still have the belly flab unfortunately. I need to increase cardio, and change up the diet some, but honestly, I am not too bad with my diet, so I’m a little frustrated.
These researchers took saliva samples from recreational women athletes before and after playing 10 minutes of flag football. The data showed that this short, intense burst of competitive sport triggered the immediate release of testosterone. Interestingly, the subjects' mental state also contributed to the data. Self-rated performance scores were directly related to testosterone levels.
This product is to be taken once daily on an empty stomach. Is there a particular time frame when food can be eaten? If I were to take this in the morning right when I wake up and then eat breakfast an hour later, is that fine? Also, mostly the only time of day my stomach is usually empty is right before going to bed. If it is taken at this time, will this affect sleep at all?
However, if you have normal testosterone levels and are looking for a boost, for strength gaining purposes, then D-Aspartic acid use may prove less fruitful. A study published in Nutrition Research showed that when the booster was given to men who resistance trained four times a week, their body composition and muscle strength was no different to men who took part in resistance training without the aid of D-Aspartic acid.
The Organon group in the Netherlands were the first to isolate the hormone, identified in a May 1935 paper "On Crystalline Male Hormone from Testicles (Testosterone)".[184] They named the hormone testosterone, from the stems of testicle and sterol, and the suffix of ketone. The structure was worked out by Schering's Adolf Butenandt, at the Chemisches Institut of Technical University in Gdańsk.[185][186]
Well, this is another area of confusion and great debate, but I don’t think it’s as confusing as it appears to be in the literature. When most doctors learned about testosterone in medical school, they learned about total testosterone, or all the testosterone in the body. But about half of the testosterone that’s circulating in the bloodstream is not available to the cells. It’s tightly bound to a carrier molecule called sex hormone–binding globulin, which we abbreviate as SHBG.
AML Test includes each of the best natural testosterone boosters discussed above as well as red wine polyphenols which function as powerful, all-natural aromatase inhibitors that lower estrogen and increase testosterone levels. These polyphenols also boost nitric oxide production which enhances vasodilation and blood flow to all regions of the body.
Tongkat ali (a.k.a. Longjack, a.k.a. Eurycoma Longifolia) is a foundational compound of Ayurveda, commonly used as an aphrodisiac. Similar to DHEA, longjack has been found to be effective in both men and women for improving libido, total and free testosterone concentrations as well as muscle mass and strength in men and women! And, unlike many of the other old world herbs commonly touted as natural testosterone boosters, longjack actually has a fair amount of human research denoting its benefits.
The chemical synthesis of testosterone from cholesterol was achieved in August that year by Butenandt and Hanisch.[187] Only a week later, the Ciba group in Zurich, Leopold Ruzicka (1887–1976) and A. Wettstein, published their synthesis of testosterone.[188] These independent partial syntheses of testosterone from a cholesterol base earned both Butenandt and Ruzicka the joint 1939 Nobel Prize in Chemistry.[186][189] Testosterone was identified as 17β-hydroxyandrost-4-en-3-one (C19H28O2), a solid polycyclic alcohol with a hydroxyl group at the 17th carbon atom. This also made it obvious that additional modifications on the synthesized testosterone could be made, i.e., esterification and alkylation.
Bisphenol-A also known under the name of BPA is a chemical compound which is very widespread for manufacturing a wide spectrum of plastic items and aluminum cans. Many studies have already proven the fact that even the smallest amount of BPA is very harmful to the human health. This compound causes hormonal imbalance and even may lead to prostate cancer.
Currently available testosterone preparations in common use include intramuscular injections, subcutaneous pellets, buccal tablets, transdermal gels and patches (see Table 2). Oral testosterone is not widely used. Unmodified testosterone taken orally is largely subject to first-pass metabolism by the liver. Oral doses 100 fold greater than physiological testosterone production can be given to achieve adequate serum levels. Methyl testosterone esters have been associated with hepatotoxicity. There has been some use of testosterone undecanoate, which is an esterified derivative of testosterone that is absorbed via the lymphatic system and bypasses the liver. Unfortunately, it produces unpredictable testosterone levels and increases testosterone levels for only a short period after each oral dose (Schurmeyer et al 1983).
Your diet is the best source of zinc; along with protein-rich foods like meats and fish, other good dietary sources of zinc include raw milk, raw cheese, beans, and yogurt or kefir made from raw milk. It can be difficult to obtain enough dietary zinc if you're a vegetarian, and also for meat-eaters as well, largely because of conventional farming methods that rely heavily on chemical fertilizers and pesticides. These chemicals deplete the soil of nutrients ... nutrients like zinc that must be absorbed by plants in order to be passed on to you.
“Our hypothesis was that testosterone would be good for the coronary arteries because we thought that by repleting testosterone to healthy levels there would be an improvement in the cholesterol panel and atherosclerosis burden. But what we found was the opposite, that atherosclerosis actually progresses faster under the influence of testosterone.”
My entire presentation was focused on 32 different ways to increase testosterone naturally, with no injections or hormone replacement protocols required. I'm not against bioidentical hormone replacement therapy (BHRT), but I do think one should explore as many natural alternatives as possible first. Or, for even more bang for the buck, pair BHRT with the tactics you'll discover in this episode.
Testosterone replacement therapy can successfully treat erectile dysfunction and loss of libido in men with low testosterone from either advancing age or hypogonadism. Although the effects of increased testosterone are more dramatic in hypogonadal men there are also benefits to the libido of men with normal gonadal, also called eugonadal, function. In a 2004 study published in the "Journal of Endocrinology and Metabolism," researchers found that increasing peak testosterone levels to between 400 and 500 percent above baseline in subjects resulted in a significant increase in sexual arousability over placebo subjects.

TestRX is a relative newcomer to the testosterone booster supplement market but don’t write it off because of that. We like the broad range of quality ingredients that appear to be thoughtfully selected to deal head on with the range of symptoms resulting from Low T. The following TestRX review will look at this formula closely and give you the facts! READ THE REVIEW
Most studies support a link between adult criminality and testosterone, although the relationship is modest if examined separately for each sex. Nearly all studies of juvenile delinquency and testosterone are not significant. Most studies have also found testosterone to be associated with behaviors or personality traits linked with criminality such as antisocial behavior and alcoholism. Many studies have also been done on the relationship between more general aggressive behavior/feelings and testosterone. About half the studies have found a relationship and about half no relationship.[66] However, later it was found out that testosterone activates dominant, aggressive behavior if at the same time a person has high testosterone and low levels of cortisol in the blood. Conversely, a high level of testosterone and high levels of cortisol do not stimulate dominant behavior. Because cortisol inhibits the action of testosterone.[67][68][69][70] This is probably why the results of the experiments were inconsistent.

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]
Benefits: Ashwagandha a wonderful herb originating from India is also called the Indian Ginseng because of it’s regard as a powerful aphrodisiac. Ashwagandha roots when consumed it increases sexual powers. These sexual powers include maintaining a stronger erection, longevity, enhanced sexual feeling. It also enhances fertility by increasing sperm count and quality. Ashwaganda works by reducing prolactin and neutralizing free radicals which both leads to increased testosterone levels.
Testosterone is well known as the most critical anabolic, not to mention androgenic, hormone in the body. It’s what separates the men from the boys. Healthy testosterone levels are critical for guys who want to build muscle mass, boost strength, and drop body fat. Testosterone also supports sexual health and gives a competitive edge. It’s truly the alpha hormone.
A: If a health insurance company is providing coverage for a medication, including testosterone replacement therapy, they determine the final cost of the product. Costs will vary from one health insurance plan to another. To determine the costs of the testosterone replacement options, the health insurance plan should be contacted. There are various options for testosterone replacement therapy including gels, injections, patches, and tablets that dissolve under the lip. All of the formulations can be effective and each has advantages and disadvantages. The most appropriate testosterone replacement therapy depends on a variety of factors, including cost, patient preference, and tolerability. Testosterone replacement gels, such as AndroGel and Testim, are very effective and easy to administer. AndroGel and Testim can be easily applied to the skin once daily. However, the gels can be irritating to the skin and AndroGel and Testim are typically quite expensive. Testosterone replacement injections, such as Depo-Testosterone (testosterone cypionate) and Delatestryl (testosterone enanthate), are usually inexpensive. The injections are given only once every one to two weeks. The major disadvantage with injectable testosterone is that testosterone levels may be difficult to control. Levels may be too high after an injection and too low before the following injection. A testosterone replacement patch, such as Androderm, is applied every night and left on for 24 hours. Androderm can be applied to the arm, back or stomach, in an area without too much hair. Androderm can cause irritation of the skin. A testosterone tablet, Striant, is placed under the upper lip against the gums and replaced every 12 hours. Striant molds to the upper gum so that eating and drinking can occur normally. The testosterone tablet can irritate the gums and cause a bitter taste and toothache. People with low testosterone should work with their doctor or healthcare provider to find a safe, effective, and affordable testosterone replacement option for them. For more specific information, consult with your doctor or pharmacist for guidance based on your health status and current medications, particularly before taking any action. Derek Dore, PharmD

After 90 days, it seemed like the Andro Gel kind of stopped having it’s effect. Went back to see the doc, and my levels had dropped back to about 198 from high 200’s. Doc said it’s not unusual that the body gets used to it, and maybe I needed to adjust up. I switched to four pumps per day, and I felt immediate effects. Now…there is a period of ultra-horniness, and sometimes, you will feel some of the “roid rage” at some of these levels. It varies from person to person. Generally, if you are an ass, or high strung, this will amplify it. If you are pretty mellow, you may notice that every once in a while you’ll get angry at something that does matter, but again, it’s different person to person.
One thing that is often overlooked when it comes to testosterone boosters is the dosing. Test boosters aren’t like other supplements where you can just take the one dosing per day and forget about until the next day. As with any supplement, it only stays in your system for 4-8 hours. This means you need to be taking more than one dose per day. 2 doses are better but it still is not enough. If you want to keep your test levels up all day you will need to be taking at least 3 and preferably 4 doses per day to keep your testosterone levels high throughout the day and to keep them from dropping between doses. You should also be sure to take them every day and try to not miss any doses to get the most out of them.
Glad to be heard. I have been using 10 times the recommended prescription dose of injectable test over the course of 6 years. Yes, 10 times the recommended dose. I use 250 at the lowest and 1000 mgs a week and sometimes 1200 mgs weekly. I am 50 years old. I look better than 90% of the 25 year olds I see in the gym. I have had zero issues. Acne a little , testicle shrinkage maybe 15%. No big deal. My sex drive is on fire. I bench pressed 340 pound today. I weigh 195 pounds and lean and muscles defined and hard as a rock. Doctors in the USA have no clue what they are doing. They read literature and have no experience or facts about test. They prescribe 50 mgs a week. Way short of what we as men need. Everyone is different, but 250mgs weekly is what we need typically. Injectable is the way to go. Gels are a weak joke. My doctor basically told me he was scared to prescribe more than 50 mgs weekly for fear of being sued if something went wrong. I found my own source and have been on top of the world for 6 years. Father died of prostate cancer. Mine prostate is fine. Prostate cancer from test is another example of ignorance in medical field. I am living proof that one can inject 10 times the recommended rate for the better part of a decade with no probs. I do hope the medical field catches up with the times and stops relying on archaic info.
Cruciferous vegetables like broccoli are rich in indoles, anti-cancer compounds that indirectly boost testosterone production by breaking down and flushing the system of excess estrogen, which inhibits the production of male sex hormones. As men age, their estrogen levels gradually rise, while testosterone levels fall. Indoles can help strike the balance. In one study, supplementing with indole-3-carbinol from cruciferous vegetables for just 7 days cut the estrogen hormone estradiol in half for men. Another study found indole supplementation significant increased urinary excretion of estrogens among men.
Testosterone decreases body fat. Testosterone plays an important role in regulating insulin, glucose, and fat metabolism. As our T levels decrease, our body’s ability to regulate insulin, glucose, and fat metabolism decreases, which in turn causes adipose tissue (i.e. fat) to begin accumulating. To add insult to injury, that increased adipose tissue may also contribute to further decreasing testosterone levels because it converts testosterone into estrogen.
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Cross-sectional studies have not shown raised testosterone levels at the time of diagnosis of prostate cancer, and in fact, low testosterone at the time of diagnosis has been linked with more locally aggressive and malignant tumors (Massengill et al 2003; Imamoto et al 2005; Isom-Batz et al 2005). This may reflect loss of hormone related control of the tumor or the effect of a more aggressive tumor in decreasing testosterone levels. One study found that 14% of hypogonadal men, with normal digital rectal examination and PSA levels, had histological prostate cancer on biopsy. It is possible that low androgen levels masked the usual evidence of prostate cancer in this population (Morgentaler et al 1996). Most longitudinal studies have not shown a correlation between testosterone levels and the future development of prostate cancer (Carter et al 1995; Heikkila et al 1999; Stattin et al 2004) but a recent study did find a positive association (Parsons et al 2005). Interpretation of such data requires care, as the presentation of prostate cancer could be altered or delayed in patients with lower testosterone levels.
2009 had heart attack, placed coronary stent, everything okay. Put on statins to keep lipid levels down to prevent further artery blockage. One year later developed Peyronie’s disease, low sex drive, fatigue, testicles withdrawn and hurting. Testosterone level was 85. Diagnosed with hypogonadism. Started Androgel, felt normal after a couple of weeks. I believe statins is the cause of my low T, you need lipids for hormone transport. Androgel could only bring my T level in the 250 range. Switched to Axiron (better, less messy), and my T level stays around 500 range. I get samples of Testim every now and then, it has a manly woody fragrance that women like. At present, I’m feeling a little fatigue, and mild dehydration. My lab work is always normal, except my red blood cells is always on the high side, almost abnormal. Next week I am going to donate some blood, to bring my RBC count down, and see if that will help.
If you're a man who's experiencing symptoms such as decreased sex drive, erectile dysfunction, depressed mood, and difficulties with concentration and memory, and you think low testosterone may be to blame, you can have your levels tested. Since testosterone levels fluctuate throughout the day, you'll probably need more than a blood test to get a true picture of your levels.
Estrogen is important in men, but too high of a level has all sorts of negative consequences – ranging from heart attacks to prostate cancer (32 & 33). The balance between testosterone and estrogen (or estradiol) is critical for a man. If the ratio is out and estrogen starts to dominate you run into all sorts of issues – such as breast cell growth, prostate enlargement and of course lower testosterone.
Finally, related to the point about competitiveness above, studies have shown that testosterone levels not only go up before a fight or competition, they increase after each win, and this gives the winner a much higher probability of winning his next round, and the next round after that, even against evenly matched competitors. This is called the “winner-effect,” and John Coates, author of The Hour Between Dog and Wolf: Risk Taking, Gut Feelings and the Biology of Boom and Bust, explains why it works:
Late onset hypogonadism reflects a particular pathophysiology and it may not be appropriate to extrapolate results from studies concerning the effects of testosterone in treating hypogonadism of other etiology to aging males. For this reason, the age of men treated in clinical trials is certainly relevant. Other important factors include patient comorbidities and the preparation and route of testosterone replacement used in the study, which can affect the production of estrogen and dihydrotestosterone, testosterone’s active metabolites
Why do we need magnesium? Magnesium is an essential nutrient in the body that can help decrease the risk of developing osteoporosis, improve insulin sensitivity, and lower the risk of hypertension. This article looks at other health benefits of magnesium, what happens if a person has a deficiency, supplements, and how to include it in the diet. Read now
The other problem researchers run into when studying the benefits of testosterone is distinguishing between “cause” and “effect.” Is it T that’s providing all these great health benefits or does simply being healthy give you optimal levels of testosterone? It’s tricky because in some instances the answer is “both.” Testosterone (like all hormones) often plays a part in a “virtuous cycle” that regulates a whole host of  processes in our bodies — as you increase T, you get healthier; as you get healthier, your T levels rise. It can also play a part in a “vicious cycle” — as your T levels go down, your health suffers; as your health suffers, your T levels decrease even more.

Why do we need magnesium? Magnesium is an essential nutrient in the body that can help decrease the risk of developing osteoporosis, improve insulin sensitivity, and lower the risk of hypertension. This article looks at other health benefits of magnesium, what happens if a person has a deficiency, supplements, and how to include it in the diet. Read now
It is hard to know how many men among us have TD, although data suggest that overall about 2.1% (about 2 men in every 100) may have TD. As few as 1% of younger men may have TD, while as many as 50% of men over 80 years old may have TD. People who study the condition often use different cut-off points for the numbers, so you may hear different numbers being stated.
In my late 40’s I was on Androgel. I lost weight and gained muscle; became healthier over all, brighter outlook, more active, and a harder erection that had a mind of it’s own. Then I went on injectable testosterone. My numbers are normal but my weight is up even after eating less. As well everything else is shelter smelter. I intend to get back to Androgel. (this, of course, is my own personal study)
With the ever-increasing interest in IGF-1, a growing number of legal, over-the-counter supplements have emerged which are aimed at amplifying the body’s own supply of this age-reversing hormone. The most common tend to be in the form of deer antler velvet extracts, delivered as a spray, due to the naturally occurring IGF-1 contained in the velvet itself.

Forged Methyl EAA stands out as it has a special concentrated derivative of D-Aspartic Acid (DAA) which is touted as being 50 times more effective than normal DAA. The formula is so strong that Transform supplements had to put an estrogen blocker as when your testosterone levels get boosted very high, your body will start to convert it to estrogen. It comes with a hefty price tag but many users have considered it to be hands down the strongest on the market.
While testosterone stimulates a man’s sex drive, it also aids in achieving and maintaining an erection. Testosterone alone doesn’t cause an erection, but it stimulates receptors in the brain to produce nitric oxide. Nitric oxide is a molecule that helps trigger a series of chemical reactions necessary for an erection to occur. When testosterone levels are too low, a man may have difficulty achieving an erection prior to sex or having spontaneous erections (for example, during sleep).
With the ever-increasing interest in IGF-1, a growing number of legal, over-the-counter supplements have emerged which are aimed at amplifying the body’s own supply of this age-reversing hormone. The most common tend to be in the form of deer antler velvet extracts, delivered as a spray, due to the naturally occurring IGF-1 contained in the velvet itself.
If you take a statin (cholesterol lowering medication) and you follow the 30-Day Heart Tune-Up program, there is a good chance you’ll be able to work with your doctor and over time safely stop your statin medication. Statin medications lower cholesterol, and you need cholesterol to make testosterone. Ask your doctor what you can do with lifestyle changes to not need a statin medication. Improving your cholesterol profile is only part of the answer. Many of the risk calculators doctors use look at tobacco use, body weight, blood pressure, blood sugar, and cholesterol. Improve all your risk factors, and often you won’t qualify for a medication!
Tarig Elraiyah, Mohamad Bassam Sonbol, Zhen Wang, Tagwa Khairalseed, Noor Asi, Chaitanya Undavalli, Mohammad Nabhan, Osama Altayar, Larry Prokop, Victor M. Montori, Mohammad Hassan Murad; The Benefits and Harms of Systemic Dehydroepiandrosterone (DHEA) in Postmenopausal Women With Normal Adrenal Function: A Systematic Review and Meta-analysis, The Journal of Clinical Endocrinology & Metabolism, Volume 99, Issue 10, 1 October 2014, Pages 3536–3542,
I’m telling you all of this because no matter who you are, keeping your testosterone levels balanced is more important now than ever before. Modern living has not been kind to our hormones. In American men, serum testosterone levels have declined by about 1% each year for the past 30 years [5], and you can make a few educated guesses about why. Hormone-disrupting chemicals are more prevalent than ever before, physical activity is less and less common, veganism is popular (I was a raw vegan for a while), and many doctors insist on pushing a low-fat, low-cholesterol diet for health (by the way, the concept of a low-fat diet began in the mid-70s, shortly before the nationwide testosterone decline. It could be a coincidence, but I doubt it).

This post can absolutely change your life, and probably help you avoid some pitfalls. Like shrunken balls. (I am not an expert in the synthetic anabolic testosterone drugs used by bodybuilders — they carry lots of risks but pack a big punch if you want to get swole. Bulletproof is all about having massive clean energy, looking good, and living a very long time…so anabolic steroids aren’t on my roadmap.)

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).