Our bodies make testosterone while we sleep. In one study, men who got five hours of sleep a night had testosterone levels 10 to 15 percent lower than when they got a solid eight hours. The study, conducted by the University of Chicago, found that skimping on sleep reduced the men’s T levels by an amount equivalent to aging 10 or more years. While it can be challenging to change your sleep habits, says Natasha Turner, ND, you can “start going to bed 15 minutes earlier each week until you reach your target time.”

Some of the effects of testosterone treatment are well recognised and it seems clear that testosterone treatment for aging hypogonadal men can be expected to increase lean body mass, decrease visceral fat mass, increase bone mineral density and decrease total cholesterol. Beneficial effects have been seen in many trials on other parameters such as glycemic control in diabetes, erectile dysfunction, cardiovascular risk factors, angina, mood and cognition. These potentially important effects require confirmation in larger clinical trials. Indeed, it is apparent that longer duration randomized controlled trials of testosterone treatment in large numbers of men are needed to confirm the effects of testosterone on many aspects of aging male health including cardiovascular health, psychiatric health, prostate cancer and functional capacity. In the absence of such studies, it is necessary to balance risk and benefit on the best available data. At the present time the data supports the treatment of hypogonadal men with testosterone to normalize testosterone levels and improve symptoms. Most men with hypogonadism do not have a contraindication to treatment, but it is important to monitor for adverse consequences including prostate complications and polycythemia.
Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than testosterone, so that its androgenic potency is about 5 times that of T.[118] The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.
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I know the experiment didn’t simply bring me back to my pre-August levels because of the fact that when I learned that the original test I took can sometimes overestimate your T levels, I took a more accurate test around four months after the start of the experiment (I’ve continued the lifestyle changes made during the experiment) and my total T had gone up again to 826.9 ng/dL.
In high-fat high-furctose fed rats, ginger neutralized diet induced impairment in glucose regulation, dyslipidemia, and oxidative stress [28]. This observed anti-diabetic activity of ginger powder is credited to two active components: 6-paradol and 6-shogaol [29]. They both exhibit potent activity in stimulating glucose utilization by 3T3-L1 adipocytes and C2C12 myotubes. In the high-fat diet mouse model, 6-paradol decreased blood glucose, cholesterol and body weight.
Oral/buccal (by mouth). The buccal dose comes in a patch that you place above your incisor (canine or "eyetooth"). The medication looks like a tablet but you should not chew or swallow it. The drug is released over 12 hours. This method has fewer harmful side effects on the liver than if the drug is swallowed, but it may cause headaches or cause irritation where you place it.

Testosterone, historically believed to be important only for male sexual function, has over the past decades transformed from niche hormone to multi-system player.22 There is increasing recognition of the harmful consequences of hypogonadism (also known as testosterone deficiency) wide spectrum of beneficial health effects of testosterone therapy and.23, 24
Fenugreek is often found in Indian, Turkish, and Persian cuisine. Multiple studies have found it to improve testosterone levels, and in particular, sexual performance. Scientists at Babu Banarasi Das University and King George’s Medical University in India have found that fenugreek improved testosterone levels. Testosterone levels increased for 90% of the volunteers, sperm morphology (the size and shape of sperm) improved for 14.6%, and more than 50% of volunteers experienced improvements in mental alertness, mood, and libido.
I noticed that you say that those that have prostate cancer should not have testosterone replacement therapy, Why-in light of the studies that say that there is no danger from testosterone therapy to one that had/has prostate cancer? If this is your opinion do you have any suggestions as to what I should do about my symptoms? Does testosterone replacement therapy actually do anything?
As you cut these dietary troublemakers from your meals, you need to replace them with healthy substitutes like vegetables and healthy fats (including natural saturated fats!). Your body prefers the carbohydrates in micronutrient-dense vegetables rather than grains and sugars because it slows the conversion to simple sugars like glucose, and decreases your insulin level. When you cut grains and sugar from your meals, you typically will need to radically increase the amount of vegetables you eat, as well as make sure you are also consuming protein and healthy fats regularly.
Intramuscular testosterone injections were first used around fifty years ago. Commercially available preparations contain testosterone esters in an oily vehicle. Esterification is designed to retard the release of testosterone from the depot site into the blood because the half life of unmodified testosterone would be very short. For many years intramuscular preparations were the most commonly used testosterone therapy and this is still the case in some centers. Pain can occur at injection sites, but the injections are generally well tolerated and free of major side effects. Until recently, the available intramuscular injections were designed for use at a frequency of between weekly and once every four weeks. These preparations are the cheapest mode of testosterone treatment available, but often cause supraphysiological testosterone levels in the days immediately following injection and/or low trough levels prior to the next injection during which time the symptoms of hypogonadism may return (Nieschlag et al 1976). More recently, a commercial preparation of testosterone undecanoate for intramuscular injection has become available. This has a much longer half life and produces testosterone levels in the physiological range throughout each treatment cycle (Schubert et al 2004). The usual dose frequency is once every three months. This is much more convenient for patients but does not allow prompt cessation of treatment if a contraindication to testosterone develops. The most common example of this would be prostate cancer and it has therefore been suggested that shorter acting testosterone preparations should preferably used for treating older patients (Nieschlag et al 2005). Similar considerations apply to the use of subcutaneous implants which take the form of cylindrical pellets injected under the skin of the abdominal wall and steadily release testosterone to provide physiological testosterone levels for up to six months. Problems also include pellet extrusion and infection (Handelsman et al 1997).

Androgens may modulate the physiology of vaginal tissue and contribute to female genital sexual arousal.[48] Women's level of testosterone is higher when measured pre-intercourse vs pre-cuddling, as well as post-intercourse vs post-cuddling.[49] There is a time lag effect when testosterone is administered, on genital arousal in women. In addition, a continuous increase in vaginal sexual arousal may result in higher genital sensations and sexual appetitive behaviors.[50]


Male sex characteristics greatly depend on testosterone synthesis in your body. If you keep the levels of this hormone normal, you will prevent sexual potency issues. Accordingly, the elevation of testosterone levels helps combat the impairment of erectile function. The levels of this hormone also affect male fertility. If these levels grow, fertility improves. Aging has a negative impact on testosterone secretion. Such hormonal imbalance is inevitable and permanent. But it’s still possible to positively change the situation and stimulate hormone production by using the high-quality testosterone boosters.
Herbalists have used _Trifolium pratense_, red clover, to treat menopausal symptoms like hot flashes. The mechanisms underlying these effects remain unknown. Testosterone decreases hot flashes in some postmenopausal women, so red clover may work in this way. A 2015 paper in the Avicenna Journal of Phytomedicine reviewed the literature testing this idea.
I am a 43 year old and have undergone pituitary sectioning/surgery twice. Since then i have been using the testoterone gel daily for 12 years without any problem. However, i still have pituitary tumor and also diagnosed with colon cancer. I am thinking of stopping the HRT because i felt it is worsening the illness. I would be glad if you could advice me of the risk of stopping the treatment.

Looking for ingredients that work in the realm of supplements can be like finding a needle in a haystack. Testosterone boosters, like all dietary supplements, are not approved by the Food and Drug Administration prior to marketing. This lack of oversight dates back to the 1994 Dietary Supplement Health and Education Act (DSHEA), which stipulated that purveyors of supplements weren’t required to prove the safety of their products or the veracity of what’s on the labels to the FDA before listing them for sale. Often, there isn’t a lot of scientific backing behind an ingredient, or research has been done solely on animals, not humans.


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].

BSN Evotest the next ranked testosterone booster and is a unique option in that it’s available in both capsule and powdered drink form. For those who dislike swallowing pills, this will be a better route to go. There are mixed reports on the taste quality of the product, however, this is an individual preference and should not be something that deters you from purchasing it. It mixes fairly well by most reports, so is something that you should be able to easily take with you to the gym for use during the workout session.
Bodybuilding.com sells science-backed testosterone support from top brands so you can continue to crush your goals. Our customer reviews will give you a snapshot of how each of these products works on real people living real lives, so you can make the best decision for your body. Ready to feel powerful again? Let’s find the test booster that’s right for you.

Men who watch a sexually explicit movie have an average increase of 35% in testosterone, peaking at 60–90 minutes after the end of the film, but no increase is seen in men who watch sexually neutral films.[43] Men who watch sexually explicit films also report increased motivation, competitiveness, and decreased exhaustion.[44] A link has also been found between relaxation following sexual arousal and testosterone levels.[45]

The content here is for information purposes only. By delivering the information contained herein is does not mean preventing, diagnosing, mitigating, treating or curing any type of medical condition or disease. When beginning any natural supplementation regiment or integrative treatment, the advice of professionally licensed healthcare providers is advisable to seek.
In decades past, this essentially meant that once your body hit a certain age, it no longer kept up with the young at heart. Luckily, today there is a variety of solutions to combat declining testosterone levels, including Test Boosters, dietary supplements which are formulated to help naturally stimulate the body’s production of testosterone. Sounds good, but not sure where to start? We’ve compiled the Top 10 Test Boosters for 2018 to help you make the best choice.

Shilajit in its natural state has no chemical definition. In order to yield a consistent and efficacious form of shilajit, the shilajit is obtained from carefully selected rocks and is put through a patented technology where it is purified and standardized. This form of shilajit is now assured of optimal levels of bioactive components such as fulvic acid and dibenzo-pyrones, and is known as the patented PrimaVie.


Feeling low energy, lack of enthusiasm, but not so much on the sexual side, seems okay. At age 63 started an exercise program. nothing seem to help bring me back, so had my blood test at age 64. 150. 6 months later 165. My doctor started me on testosterone patches after a heart and prostate exam. Now two months into program, now using the gel, there seems little change. Disappointed. I am guess my next blood test will show less than 200. I am disappointed sufficiently to decide not to continue the program. I mean, the drugs cost $500 a month, although my cost is less. I guess my question is if I quit the program, will my body return to its normal, or will it be worse. i can live with a low normal, but less would not not be acceptable.
In addition to its role as a natural hormone, testosterone is used as a medication, for instance in the treatment of low testosterone levels in men and breast cancer in women.[10] Since testosterone levels decrease as men age, testosterone is sometimes used in older men to counteract this deficiency. It is also used illicitly to enhance physique and performance, for instance in athletes.
“This study establishes testosterone levels at which various physiological functions start to become impaired, which may help provide a rationale for determining which men should be treated with testosterone supplements,” Finkelstein says. “But the biggest surprise was that some of the symptoms routinely attributed to testosterone deficiency are actually partially or almost exclusively caused by the decline in estrogens that is an inseparable result of lower testosterone levels.”
Looking at the ingredients and we see that they used a nice dose of D-Aspartic Acid which we have already talked about how much we like that. They also used a good dose of Fenugreek which boosts testosterone and enhances libido as well as Ginseng Extract which is a natural aphrodisiac. They also use Zinc Gluconate which is a solid testosterone booster and also has shown to be a bit of an aphrodisiac itself.
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
Ben has mentioned APOE many times, as in this podcast, with the reference in this transcript as something like 34/44. I’ve always assumed that meant a number of different genes that related to APOE having the homozygous or heterzygous mutations. I’ve only been able to find one rs in my 23andme raw data that seems meaningful to this, rs429358. How do you all figure out your APOE status? Are you getting this from one of the other companies that analyzes part of your raw data for you?
Testosterone levels peak by early adulthood and drop as you age—about 1% to 2% a year beginning in the 40s. As men reach their 50s and beyond, this may lead to signs and symptoms, such as impotence or changes in sexual desire, depression or anxiety, reduced muscle mass, less energy, weight gain, anemia, and hot flashes. While falling testosterone levels are a normal part of aging, certain conditions can hasten the decline. These include:
In essence, there are two types of testosterone boosters, namely natural and synthetic supplements. Anabolic steroids which are under the synthetic category are known to deliver positive results as well as nasty side effects. It is due to this reason that an increasing number of bodybuilders and athletes are now utilizing safer testosterone boosters.
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.
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.

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:
Feeling low energy, lack of enthusiasm, but not so much on the sexual side, seems okay. At age 63 started an exercise program. nothing seem to help bring me back, so had my blood test at age 64. 150. 6 months later 165. My doctor started me on testosterone patches after a heart and prostate exam. Now two months into program, now using the gel, there seems little change. Disappointed. I am guess my next blood test will show less than 200. I am disappointed sufficiently to decide not to continue the program. I mean, the drugs cost $500 a month, although my cost is less. I guess my question is if I quit the program, will my body return to its normal, or will it be worse. i can live with a low normal, but less would not not be acceptable.
Vitamin C (unnecessary). I don’t know where I first heard about vitamin C’s supposed T-boosting benefits, but it’s one of those things you see all over the internet when you Google “how to increase testosterone.” Without trying to find the research that backs up that claim, I took a vitamin C supplement during my experiment. I later found some research that suggests that vitamin C does increase testosterone levels in diabetic mice, but because I wasn’t diabetic (nor a mouse), I’m not sure how much the vitamin C helped. I’ve actually stopped taking vitamin C supplements. I’m likely getting more than enough with my diet. Unless you have diabetes, you probably won’t see much benefit from this supplement. Don’t waste your money.
The brain is also affected by this sexual differentiation;[13] the enzyme aromatase converts testosterone into estradiol that is responsible for masculinization of the brain in male mice. In humans, masculinization of the fetal brain appears, by observation of gender preference in patients with congenital diseases of androgen formation or androgen receptor function, to be associated with functional androgen receptors.[99]
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.

Made many mistakes growing up. Late highschool, small group of guys tried Testosterone and obviously it worked great on all levels especially on the football field etc. College years we did it again and again but not anywhere near the levels of body builders we knew and saw at the gym. When it became harder to find, then….. poof it became “legal” in the form of Pro-hormones. Great right? Not so. It worked but it also worked on everything else in a negative way. Mainly liver toxicity that I noticed and just the general idea of not really knowing what was in it. When I was 38 I had a bad event with diverticulitis. I was hospitalized for 4 days and it was horrible. This is in an infection in a diverticula that forms in your intestines. It was so bad and fast that it spread with a rapid onset of epididymitis ( infection on the epididymis of your testical). After the hospital I went see my gastro who was a board member of a large anti aging group of doctors. We did bloodwork and My testosterone levels were lower than a woman! Like 110. He also explained to me that I had probably never fully recovered normal test levels from my last “get in shape” run with pro hormones 2 years before and it probably played a part in the weakening of my intestinal wall and immune system and after discussion I realized that I had exhibited all of the text book effects of low T to the letter. After spilling my guts to my doctor we decided upon the gel. It worked great but having kids around I was worried about it affecting them so we switched to in ejections taken every 2 weeks of cypionate 200mg and my wife helps me with that at home and I never stray from the regime . My levels are around 700 to 750 and basically PSA that is non existent. I am now 41 and feel great , go to Doctor twice a year for bloodwork and all is well. My doctor also tells me that in his opinion our environmental factors play a huge role in this, meaning hormones in meats, milks, public water etc. and because of that together with “Poor decision making (me in highschool, college etc) America is in the midst of an epidemic that is being under advertised and overlooked. I constantly read up on the latest info I can find and I liked reading this and your posts. Sometimes I feel guilty because I get comments on how I look and my energy levels and I wonder is this too good to be true? But if I am following a strict regiment and bloodwork reports good things…. Do I need to worry about anything else??? This is my story and I have never shared it with ANYONE other than my wife. Big move for me!! Last point……. This is a generalization but…….all women take hormones. It’s is universally accepted and part of a woman’s life without a doubt. Why is it Taboo to publicly discuss men and hormones? I guarantee if you are a man 35 and above and you did dumb things like me and or exhibit symptoms of low T, do yourself a huge favor and go see a doctor and get blood work done. More than likely you have it! I still hide all of this and I don’t want to shout it out because I feel embarrassed. WHY? Enough already!!!!


Androgens may modulate the physiology of vaginal tissue and contribute to female genital sexual arousal.[48] Women's level of testosterone is higher when measured pre-intercourse vs pre-cuddling, as well as post-intercourse vs post-cuddling.[49] There is a time lag effect when testosterone is administered, on genital arousal in women. In addition, a continuous increase in vaginal sexual arousal may result in higher genital sensations and sexual appetitive behaviors.[50]
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.
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.
Our bodies need zinc to make testosterone. Zinc also blocks the action of aromatase, the enzyme that converts testosterone to estrogen. Oysters offer the highest amount of zinc per serving of any food. Just six oysters contain about 500 percent of the mineral’s recommended daily allowance (RDA). Other zinc-rich foods include lean meats and spinach.
Testosterone is necessary for normal sperm development. It activates genes in Sertoli cells, which promote differentiation of spermatogonia. It regulates acute HPA (hypothalamic–pituitary–adrenal axis) response under dominance challenge.[22] Androgen including testosterone enhances muscle growth. Testosterone also regulates the population of thromboxane A2 receptors on megakaryocytes and platelets and hence platelet aggregation in humans.[23][24]
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

Findings that improvements in serum glucose, serum insulin, insulin resistance or glycemic control, in men treated with testosterone are accompanied by reduced measures of central obesity, are in line with other studies showing a specific effect of testosterone in reducing central or visceral obesity (Rebuffe-Scrive et al 1991; Marin, Holmang et al 1992). Furthermore, studies that have shown neutral effects of testosterone on glucose metabolism have not measured (Corrales et al 2004), or shown neutral effects (Lee et al 2005) (Tripathy et al 1998; Bhasin et al 2005) on central obesity. Given the known association of visceral obesity with insulin resistance, it is possible that testosterone treatment of hypogonadal men acts to improve insulin resistance and diabetes through an effect in reducing central obesity. This effect can be explained by the action of testosterone in inhibiting lipoprotein lipase and thereby reducing triglyceride uptake into adipocytes (Sorva et al 1988), an action which seems to occur preferentially in visceral fat (Marin et al 1995; Marin et al 1996). Visceral fat is thought to be more responsive to hormonal changes due to a greater concentration of androgen receptors and increased vascularity compared with subcutaneous fat (Bjorntorp 1996). Further explanation of the links between hypogonadism and obesity is offered by the hypogonadal-obesity-adipocytokine cycle hypothesis (see Figure 1). In this model, increases in body fat lead to increases in aromatase levels, in addition to insulin resistance, adverse lipid profiles and increased leptin levels. Increased action of aromatase in metabolizing testosterone to estrogen, reduces testosterone levels which induces further accumulation of visceral fat. Higher leptin levels and possibly other factors, act at the pituitary to suppress gonadotrophin release and exacerbate hypogonadism (Cohen 1999; Kapoor et al 2005). Leptin has also been shown to reduce testosterone secretion from rodent testes in vitro (Tena-Sempere et al 1999). A full review of the relationship between testosterone, insulin resistance and diabetes can be found elsewhere (Kapoor et al 2005; Jones 2007).
The effect excess testosterone has on the body depends on both age and sex. It is unlikely that adult men will develop a disorder in which they produce too much testosterone and it is often difficult to spot that an adult male has too much testosterone. More obviously, young children with too much testosterone may enter a false growth spurt and show signs of early puberty and young girls may experience abnormal changes to their genitalia. In both males and females, too much testosterone can lead to precocious puberty and result in infertility. 
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