Here’s one proof: in a number of British rivers, 50 percent of male fish were found to produce eggs in their testes. According to EurekAlert,3 EDCs have been entering rivers and other waterways through sewage systems for years, altering the biology of male fish. It was also found that fish species affected by EDCs had 76 percent reduction in their reproductive function.

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.
Decreased testosterone production in men with rheumatoid arthritis is a common finding (Stafford et al 2000), and it is now generally recognized that androgens have the capacity to suppress both the hormonal and cellular immune response and so act as one of the body’s natural anti-inflammatory agents (Cutolo et al 2002). This known anti-inflammatory action of testosterone has led to studying the effect of testosterone therapy in men with rheumatoid disease. Although not all studies have reported positive effects of testosterone treatment (Hall et al 1996), some studies do demonstrate an improvement in both clinical and chemical markers of the immune response (Cutolo et al 1991; Cutolo 2000). This observation would go along with more recent evidence that testosterone or its metabolites protects immunity by preserving the number of regulatory T cells and the activation of CD8+ T cells (Page et al 2006).
That there is an association between depression and testosterone concentration seems possible because of the observation that depression may be associated with reduced testosterone concentrations, hypogonadal men may have their symptoms of depression relieved by TRT and that testosterone itself may have anti-depressant properties (Pope et al 2003). The evidence, however, is inconsistent. Seidman and colleagues (2002), for example, found that there was no relationship between testosterone and depression but there was an association of testosterone with dysthymia. McIntyre and colleagues (2006), on the other hand, found that middle-aged men with depression did have a reduction in bio-available testosterone.

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.
“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!”

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.
Aromatase inhibitors can boost testosterone on their own, but they can also complement other testosterone boosters. If you take a supplement that increases testosterone without inhibiting the aromatase enzyme (through hypothalamic stimulation, for instance), you may find yourself with more estradiol than you need, a situation that taking an aromatase inhibitor may remedy.
Likewise, the amino acids in a protein-rich diet play a big role in both testosterone and muscle growth. As Chris Lockwood, Ph.D., explains, "When combined with training, which increases the sensitivity of androgen receptors, and the consumption of essential amino acids necessary to support protein synthesis, the effects of testosterone on muscle and performance is significantly amplified."[3,4]
Zaima, N., Kinoshita, S., Hieda, N., Kugo, H., Narisawa, K., Yamamoto, A., ... Moriyama, T. (2016, September). Effect of dietary fish oil on mouse testosterone level and the distribution of eicosapentaenoic acid-containing phosphatidylcholine in testicular interstitium. Biochemistry and Biophysics Reports, 7, 259–265. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5613343/
That testosterone decreases with age has been clearly established by many studies over many years in several different populations of men (Harman et al 2001; Feldman et al 2002; Araujo et al 2004; Kaufman and Vermeulen 2005). Of even greater significance is the steeper fall of the most biologically active fraction of total testosterone, non-sex hormone binding globulin (SHBG)- bound testosterone, or bioavailable testosterone (bio-T). The classical, but not the only approach to measuring bio-T, is to precipitate out SHBG (and hence the testosterone which is strongly bound to it as well) and measure the remainder as total testosterone (Tremblay 2003). Vermeulen et al (1999) have devised a less tedious and less expensive method of measuring a surrogate for bio-T, namely calculated bio-T, inserting total T, albumin, SHBG and a constant into a mathematical formulation. There is a strong correlation between actual bio-T and calculated bio-T (Emadi-Konjin et al 2003).
Testosterone is a steroid from the androstane class containing a keto and hydroxyl groups at the three and seventeen positions respectively. It is biosynthesized in several steps from cholesterol and is converted in the liver to inactive metabolites.[5] It exerts its action through binding to and activation of the androgen receptor.[5] In humans and most other vertebrates, testosterone is secreted primarily by the testicles of males and, to a lesser extent, the ovaries of females. On average, in adult males, levels of testosterone are about 7 to 8 times as great as in adult females.[6] As the metabolism of testosterone in males is more pronounced, the daily production is about 20 times greater in men.[7][8] Females are also more sensitive to the hormone.[9]
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.

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]


This supplier is located in north sumatra (but they ship from Amazon via the U.S). They harvest the tongkat ali from the sumatra jungle and use roots of trees >10 years of age. I know this supplier is the best because he used to purchase from Tongkatali.org, which if you search Google you will find is the most reputable stuff. But he tests every batch before sending it out and became unhappy with the quality of their product. He now purchases from a new supplier who get tongkat ali extract from the same jungle, with the same extraction process, but who performs chemical and microbiological analysis of every batch they produce, which brings me peace of mind.
There are numerous studies that show that Tribulus does not increase testosterone levels, and provides no assistance in increasing muscle mass or strength. I one of the two group of rugby players were put on the herb or a placebo. At the end of the experiment, there were zero changes in testosterone levels in the Tribulus group. Says a lot. [Source]
Epidemiological evidence supports a link between testosterone and glucose metabolism. Studies in non-diabetic men have found an inverse correlation of total or free testosterone with glucose and insulin levels (Simon et al 1992; Haffner et al 1994) and studies show lower testosterone levels in patients with the metabolic syndrome (Laaksonen et al 2003; Muller et al 2005; Kupelian et al 2006) or diabetes (Barrett-Connor 1992; Andersson et al 1994; Rhoden et al 2005). A study of patients with type 2 diabetes using measurement of serum free testosterone by the gold standard method of equilibrium dialysis, found a 33% prevalence of biochemical hypogonadism (Dhindsa et al 2004). The Barnsley study demonstrated a high prevalence of clinical and biochemical hypogonadism with 19% having total testosterone levels below 8 nmol/l and a further 25% between 8–12 nmol/l (Kapoor, Aldred et al 2007). There are also a number longitudinal studies linking low serum testosterone levels to the future development of the metabolic syndrome (Laaksonen et al 2004) or type 2 diabetes (Haffner et al 1996; Tibblin et al 1996; Stellato et al 2000; Oh et al 2002; Laaksonen et al 2004), indicating a possible role of hypogonadism in the pathogenesis of type 2 diabetes in men. Alternatively, it has been postulated that obesity may be the common link between low testosterone levels and insulin resistance, diabetes and cardiovascular disease (Phillips et al 2003; Kapoor et al 2005). With regard to this hypothesis, study findings vary as to whether the association of testosterone with diabetes occurs independently of obesity (Haffner et al 1996; Laaksonen et al 2003; Rhoden et al 2005).
Dr. Anthony’s Notes: DHEA is a powerful supplement for testosterone, energy, and overall well-being in our older Fit Fathers. A small dose of 25-50mg/day is enough to exert noticeable benefits. This supplement is over-the-counter. Verdict: this is one of the testosterone supplements that work. How To Take DHEA: Take 25-50mg once per day with food. Special Medical Note: DHEA is a MILD CYP3A4 inhibitor (a liver enzyme that processes MANY very common medications). This is the same isoenzyme that Grapefruit inhibits – albeit DHEA inhibits to a much weaker degree. If you’ve ever heard “don’t eat grapefruit with your Lipitor (cholesterol medication)”… this is the reason why. When we inhibit the CYP3A4 enzyme, more of the medications you're taking circulates (it’s not metabolized as fast). Check with your doctor for medication interactions before using DHEA.
It sounds like a creature from Jurassic World, but this plant is worth learning to pronounce, especially if you haven’t had great sex since dinosaurs roamed the earth. A 2012 study showed that consuming six grams of tribulus root for 60 days improved erections and frequency of sex in men with low sperm counts. It also reduced sexual fatigue. Furthermore, their testosterone jumped by a whopping 16%. “Trib,” as it’s called, is thorny and bitter, so look to a supplement for consuming it. Epiq’s Quad Test includes Tribulus terrestris. (epiqresults.com)

Tailor the above recommendations to your personal needs and lifestyle. If you’re a vegetarian drop the bacon and steak, but keep the whey protein and eggs. If you have an injury that prevents you from heavy weightlifting, move as much as you can in the way that you can. There are no studies out there which can tell you exactly what will happen if you do X and Y, but not Z. And I certainly can’t tell you either. Don’t be afraid of self-education – that’s how I learned all this – and embrace the idea of conducting your own experiment and being your own test subject. Incorporate as many of the recommendations above as you’re comfortable with, consult your doctor, and track your results.
A notable study out of Wayne State University in Indiana found that older men who had a mild zinc deficiency significantly increased their testosterone from 8.3 to 16.0 nmol/L—a 93 percent increase—following six months of zinc supplementation. Researchers of the study concluded that zinc may play an important role in modulating serum testosterone levels in normal healthy men.6
Some boys even develop enlarged testicles and penis, armpit or pubic hair, as well as facial hair as early as age nine! Early puberty is not something to be taken lightly because it can significantly influence physical and psychological health, including an increased risk of hormone-related cancers. Precocious sexual development may also lead to emotional and behavioral issues, such as:

Testoripped is one of the best testosterone pills we’ve ever seen. The powerful muscle-building, fat-burning,and testosterone-boosting ingredients combine to make a powerful pill no man looking to boost their testosterone should ignore. Testoripped is proven to deliver incredibly fast strength, enormous power, and improved muscle. To get the definition most men are missing, Testoripped strips away fat and builds muscle so your ripped physique is revealed.
Many studies demonstrate an improvement in mood of hypogonadal men treated with testosterone (Wang et al 1996; Azad et al 2003). The relationship between testosterone status and mood, particularly depression, remains unresolved. Using Beck’s Depression Inventory, Barrett-Connor and colleagues found that the depression score worsened as men aged, exactly at a time when testosterone levels are decreasing (Barrett-Connor et al 1999). Pope and colleagues found that testosterone treatment in men with refractory depression lowered the Hamilton Depression rating scale and the Clinical Global Impression severity rating (Pope et al 2003). The Beck Depression Inventory remained unchanged in Pope’s study.

There are studies that show Soy consumption in humans leads to lower sperm count, but unfortunately they did not look at testosterone levels in the study (40). This (41) particular study compared the estrogen production of men drinking soy protein to those drinking whey. After two weeks they found the estradiol levels were equal, however soy drinkers had LOWER Testosterone levels and HIGHER cortisol levels (both bad).
It is a natural hormone present in the body known as Dehydroepiandrosterone (DHEA). It reduces the estrogen levels while boosting testosterone levels. It has been in use since so long to raise testosterone levels. Among all supplements, it is one of the famous and many researchers are working on it to tell how it stimulates testosterone production. It is banned for athletes and professional players.
Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256]

Tribulus terrestris is an ingredient commonly presented as improving testosterone levels, but has not been found to be more effective than a placebo or possess any testosterone increasing properties. WebMD cautions that it interferes with Lithium and diabetes medications, and in general, not enough is known about tribulus terrestris to recommend a dosage for anyone.

This herb, used for centuries in foods, even poultices, was reported in the International Journal of Sport Nutrition and Exercise Metabolism to have reduced body fat and improved total testosterone levels versus a placebo in a double-blind trial. Fenugreek may also be helpful if you feel your sex drive is on the wane, as other research has found it can boost libido. You can get it in curries (it’s used to flavor them) and teas, or as a supplement in TestroVax, by Novex Biotech, which promises to boost testosterone levels 42% in 12 days. (novexbiotech.com)

Before we get into the topic, let’s jog our memory on what testosterone is. The human body is a system made of many components, each with a specific function targeting a specific area that affects our lives. Just like how the brain is associated with mentality, thinking, and rationalization and the heart is associated with blood flow and sentimentality, testosterone are hormones associated with a wide variety of body functions, predominantly sex drive, metabolism, muscle growth, and a general sense of well-being in men (women also have testosterone albeit in low levels)
We start with plastic. A lot of plastic contains bisphenol A (BPA); BPA is a weak synthetic estrogen. Like many other chemicals used in making plastics, BPA is a hormone disruptor and can block or mimic hormones and how they act in the body (34). If you think you’re safe with BPA plastic, think again. Research shows that BPA free plastic has similar estrogen-like effects on the body.

In non-human primates, it may be that testosterone in puberty stimulates sexual arousal, which allows the primate to increasingly seek out sexual experiences with females and thus creates a sexual preference for females.[39] Some research has also indicated that if testosterone is eliminated in an adult male human or other adult male primate's system, its sexual motivation decreases, but there is no corresponding decrease in ability to engage in sexual activity (mounting, ejaculating, etc.).[39]


"I'm 53 years old and my passion is surfing the oceans worldwide – big waves. Since taking Andro400, I'm now down to my ideal weight – from 185 to 175 now which is probably a net 15 pound loss, taking into account that the increased muscle I have now is heavier than the fat it replaced. My energy level is up. I feel strong and more physically fit in general. Also, from surfing I have been injured many times – for example I've broken my neck and pelvis among other things. Taking Andro400, I have much less pain overall – and I've been able to take less pain medication and anti-inflammatory drugs.”
Acne and Allergic Reactions: The testosterone is universally regarded as one of the triggering factors for acne. It stimulates the activity of oil glands making the skin more oily and vulnerable to acne. This body hormone might also cause allergic reactions, such as hives, rash, difficulty breathing, itching, chest tightness, and big swelling of the facial parts.

"I am so thankful to your company. I have lost 50 lbs. and went from a size 38 waist to an unbelievable 30! I am 56 years old, and now with Andro 400, I feel like I am 25 again. I was taking ramipril for high blood pressure and celebrex for my arthritis. Gone!!! My doctor has not seen a transformation like mine ever! Exercise used to be a chore -- now I have the energy to jog, exercise and be intimate with my partner when we share our love for each other. My mood has changed. I don't get stressed out anymore. I'm so happy now. I'm just a completely different man! Thank you, thank you, thank you!"
^ Jump up to: a b Lazaridis I, Charalampopoulos I, Alexaki VI, Avlonitis N, Pediaditakis I, Efstathopoulos P, Calogeropoulou T, Castanas E, Gravanis A (2011). "Neurosteroid dehydroepiandrosterone interacts with nerve growth factor (NGF) receptors, preventing neuronal apoptosis". PLoS Biol. 9 (4): e1001051. doi:10.1371/journal.pbio.1001051. PMC 3082517. PMID 21541365.
Because of inconclusive or conflicting results of testosterone treatment studies reported in the literature, Rabkin and colleagues (2004) undertook a comparison study among testosterone, the anti-depressant, fluoxetine, and placebo in eugonadal HIV positive men. They found that neither fluoxetine nor testosterone were different from placebo in reducing depression, but that testosterone did have a statistically significant effect in reducing fatigue. It is note-worthy that fatigue was reduced with testosterone treatment even though virtually all the men in the study had testosterone levels within the reference range.
This being my initial use of product I do find an overall improvement in mind and body "maleness" related to focused goal and strength improvements. Has it turned me into a super stud..no, but at a recent 60th birthday, increased desire has added to performance and that is what I was looking for.I have reinstated diet and exercise that also has made physical and mental health achievements Will finish current bottle, and evaluate overall products worth once completed. Further evaluation pending...

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.


Testosterone is only one of many factors that influence aggression and the effects of previous experience and environmental stimuli have been found to correlate more strongly. A few studies indicate that the testosterone derivative estradiol (one form of estrogen) might play an important role in male aggression.[66][67][68][69] Studies have also found that testosterone facilitates aggression by modulating vasopressin receptors in the hypothalamus.[70]
In accordance with sperm competition theory, testosterone levels are shown to increase as a response to previously neutral stimuli when conditioned to become sexual in male rats.[40] This reaction engages penile reflexes (such as erection and ejaculation) that aid in sperm competition when more than one male is present in mating encounters, allowing for more production of successful sperm and a higher chance of reproduction.
When you're under a lot of stress, your body releases high levels of the stress hormone cortisol. This hormone actually blocks the effects of testosterone,6 presumably because, from a biological standpoint, testosterone-associated behaviors (mating, competing, aggression) may have lowered your chances of survival in an emergency (hence, the "fight or flight" response is dominant, courtesy of cortisol).
Imagine if there was a pill that would transform your dick into an unstoppable orgasm machine; A pill that gave you the confidence to talk to any girl, because you knew one night with you and she would be begging for your cock. Women are attracted to men that can make them climax. The most PATHETIC trait a man can have is being bad at sex. But the exact opposite is also true.
While it would be nice to buy a testosterone pill from the local supplement store and have your testosterone levels go up, such a magic pill does not exist. As you can see from the above rundown, while a few supplements may be somewhat effective if your T levels are already low, none will significantly raise your testosterone above a baseline level. Thus, the basics of keeping your T levels high remain pretty simple:

This supplier is located in north sumatra (but they ship from Amazon via the U.S). They harvest the tongkat ali from the sumatra jungle and use roots of trees >10 years of age. I know this supplier is the best because he used to purchase from Tongkatali.org, which if you search Google you will find is the most reputable stuff. But he tests every batch before sending it out and became unhappy with the quality of their product. He now purchases from a new supplier who get tongkat ali extract from the same jungle, with the same extraction process, but who performs chemical and microbiological analysis of every batch they produce, which brings me peace of mind.
And then there’s also the fact that sodium bicarbonate tends to act as a molecular switch for the cyclic adenosine monophosphate (cAMP). And increased cAMP levels – as you might already know – correlate with increased T production since cAMP activates protein kinase A and serves as a secondary messenger between cells and hormones (study, study, study, study, study, study, study, study, study).
Testosterone is the primary sex hormone in men, and it is responsible for the development of many of the physical characteristics that are considered typically male. Women also produce the hormone in much smaller amounts. Testosterone, part of a hormone class known as androgens, is produced by the testicles after stimulation by the pituitary gland, which is located near the base of the brain, and it sends signals to a male's testicles (or to a woman's ovaries) that spark feelings of sexual desire. (1)
Carbs play a big part in determining your Testosterone levels. Let's start with what to avoid. First, research shows that a large serving of sugar (75g of glucose), decreased Testosterone levels by as much as 25%! (25 & 26). I know this is a pretty extreme dosage, but you may want to avoid massive servings of sugar! Also, men who have Metabolic syndrome have lower Testosterone levels (27). Metabolic syndrome is often brought about by chronic high blood sugar which leads to insulin resistance.
To get a good dietary source of selenium, you can eat shellfish or Brazilian nuts. 1-2 Brazilian nuts is enough to get 200% of your daily intake. You don’t need any more than that. Read more about increasing testosterone with Brazilian nuts here. It’s a good idea to get your selenium levels checked before hand and then adjust your diet as needed to avoid selenium toxicity.
Testosterone is a hormone that is secreted in both men and women. It is responsible for sex drive, as well as protein processing for muscle mass development and strength. Testosterone declines with age, illness and poor nutrition in both genders, though this change may be more marked in men. Synthetic hormone replacement therapy can cause adverse side effects. A natural way to raise the body’s testosterone levels safely include supplementing the diet with specific nutrients and physical exercise.
So out of all the natural testosterone boosting supplements out there I only really recommend tongkat ali extract, d-aspartic acid, and ashwagandha. There are a many others out there, but none that meet the standard that these do. And most of the other ones are actually in Testofuel. But remember, use at your own discretion. Even natural supplements can have side effects, so talk to your doctor first, and start slow.
Also, due to the intake of these synthetic substances, men start behaving in a very excited way, as well as demonstrate high levels of aggression and even violence. So, the men’s behavior may be antisocial. In addition, the men will experience breast enlargement and testicular shrinkage. The other adverse effects include hypertension, tumor growth, heart attacks and strokes, as well as development of liver disorders. It’s obvious that the numerous dangers of steroid use far outweigh a few benefits which they bring.

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.
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).
In females, this test can find the reason you’re missing periods, not having periods, or having a hard time getting pregnant. Doctors can also use it to diagnose polycystic ovary syndrome (PCOS). That’s a hormone problem that can cause irregular periods and make it hard to get pregnant. A testosterone test can also reveal if you might have a tumor in your ovaries that affects how much of the hormone your body produces.
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.
More can be learned from a large, randomized, placebo-controlled trial of finasteride treatment in 18,800 men aged 55 or more. Finasteride is a 5α-reductase inhibitor which acts to prevent the metabolism of testosterone to dihydrotestosterone (DHT) – the most active androgen in the prostate. The trial showed a greater overall incidence of prostate cancer in the control group, but men treated with finasteride were more likely to have high grade tumors (Thompson et al 2003), suggesting that reduced androgen exposure of the prostate may delay the presentation of prostate cancer and/or promote advanced disease in some other way.
Testosterone is a sex hormone that plays important roles in the body. In men, it’s thought to regulate sex drive (libido), bone mass, fat distribution, muscle mass and strength, and the production of red blood cells and sperm. A small amount of circulating testosterone is converted to estradiol, a form of estrogen. As men age, they often make less testosterone, and so they produce less estradiol as well. Thus, changes often attributed to testosterone deficiency might be partly or entirely due to the accompanying decline in estradiol.
×