Testosterone makes a contribution to nitric oxide formation. Nitric oxide, released from penile nerves stimulates guanylate cyclase which catalyzes the transformation of guanosine-5-triphosphate into 3′,5′-cyclic, guanosine monophosphate (cyclic GMP). Gyclic GMP causes vasodilatation and hence erection formation (Morelli et al 2005). The breakdown of cyclic GMP to GMP is mediated by the enzyme, phosphodiesterase type-5, the inhibitors of which (eg, sildenafil citrate) enhance erection formation and maintanence (Carson and Lue 2005).
I bought most of the ingredients for my Testosterone Salad at Whole Foods. For those curious, I added up all the ingredients and divided by six (I typically ate six of these salads in a week). The cost per salad was roughly $5. That’s about the price many folks pay every day for a crappy fast food meal. If you’re on a budget, I’m sure you could get the ingredients at Walmart and bring the cost per salad down even more.
One of the most important nutrients that can help boost testosterone levels is vitamin D3. In 2011, the results of a study published in the journal Hormone and Metabolic Research announced that vitamin D supplementation boosts testosterone naturally in overweight men by up to 30 percent. (12) This is pretty exciting because research has shown that vitamin D3 is also linked to helping to prevent and treat cancer! (13)
You should also get rid of cleaning products loaded with chemicals, artificial air fresheners, dryer sheets, fabric softeners, vinyl shower curtains, chemical-laden shampoos, and personal hygiene products. Replace them all with natural, toxin-free alternatives. Adjusting your diet can also help, since many processed foods contain gender-bending toxins. Switch to organic foods, which are cultivated without chemical interventions.

^ David KG, Dingemanse E, Freud JL (May 1935). "Über krystallinisches mannliches Hormon aus Hoden (Testosteron) wirksamer als aus harn oder aus Cholesterin bereitetes Androsteron" [On crystalline male hormone from testicles (testosterone) effective as from urine or from cholesterol]. Hoppe-Seyler's Z Physiol Chem (in German). 233 (5–6): 281–83. doi:10.1515/bchm2.1935.233.5-6.281.
Testosterone is an anabolic steroid hormone that plays a critical role in metabolism, sex drive, muscle building, mood regulation, memory & cognitive function.  Normal testosterone levels play a huge role in maintaining optimal weight as well as reducing risk of degenerative diseases such as osteoporosis, heart disease, diabetes, & certain cancers (1, 2, 3).
It seems like today it’s a badge of honor to train every day until exhaustion. The ethos is to push yourself harder and harder every day. If that’s your philosophy towards exercise, you might be sabotaging your testosterone levels (as well as your 20 Mile March). Studies have shown that overtraining can reduce testosterone levels significantly. Yes, it’s important to exercise hard, but it’s even more important to give your body rest so it can recuperate from the damage you inflicted upon it.
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.
One study looking at alcohol consumption found that increasing alcohol consumption led to a higher level of free & total testosterone compared to a non-drinking control group (20). Drinking did however lower SHBG testosterone levels, though this type of testosterone is bound to a protein meaning our bodies cannot use it to build muscle or increase our mood.
A sedentary lifestyle is another scourge for modern civilization. And this is a serious danger for men. After all, if physical activity is minimal, the testosterone levels will decrease steadily. And in this situation, strength training exercises are a proven method for raising testosterone. Thus, sports exercises always helped raise the levels of male sex hormone. As a result, the testosterone levels elevate after every workout.
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 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?
^ Southren AL, Gordon GG, Tochimoto S, Pinzon G, Lane DR, Stypulkowski W (May 1967). "Mean plasma concentration, metabolic clearance and basal plasma production rates of testosterone in normal young men and women using a constant infusion procedure: effect of time of day and plasma concentration on the metabolic clearance rate of testosterone". The Journal of Clinical Endocrinology and Metabolism. 27 (5): 686–94. doi:10.1210/jcem-27-5-686. PMID 6025472.
With the decline of ovarian function in menopause, not only do estrogen levels decline, but so does testosterone availability, since the ovaries contribute, either by direct secretion or through precursor production, about 50 percent of circulating testosterone. The other 50 percent is supplied by the adrenal glands. Many post-menopausal or oophorectomized women are symptomatic as a consequence of reduced testosterone, the leading symptom being loss of libido (Sherwin and Gelfand 1987; Simon et al 2005). There is an increasing trend toward testosterone supplementation in these women. Such supplementation may also lead, not only to increased libido, but to increased bone mineral density and an improvement in general overall sense of well-being including energy, strength, motivation and mood (Davis et al 1995; Davis et al 2000).
So if you’re intent on maximizing your testosterone levels, and/or you have applied all of the above and you’re still not satisfied with your results (which would be surprising) then you could try the below. I will point out that some of these tips may not have the scientific evidence to back them up like the previous points, but I can assure you that either I have or do use them (and have positive results), or a client has used them with pleasing results, or finally it is such a new conception that there isn’t enough evidence to prove it one way or another.
A 46 XY fetus is destined to become a male because the Y chromosome carries testicular determining gene which initiates transformation of the undifferentiated gonad into testes (Töhönen 2003). The testes subsequently produce both Mullerian Inhibiting Factor (to induce degeneration of the Mullerian system, the internal female ductal apparatus) and testosterone (to stimulate growth and development of the Wolffian system – epididymus, vas deferens, seminal vesicle and, after conversion to dihydrotestosterone (DHT) by the enzyme 5-α-reducase, the prostate gland). DHT is also the primary androgen to cause androgenization of the external genitalia.
Next, while testosterone levels do decline with age, this may simply be because the older that men get, the less they take care of themselves – they stop exercising, start putting on weight, and don’t pay as much attention to their diet. A recent study suggests that age-related T decline is not inevitable, and that if you keep living a healthy lifestyle, you can maintain healthy testosterone levels. So if you’re an older guy, try to do all you can as far as lifestyle changes before you get on the prescription T. I don’t mean doing a little cardio a few times a week, using the machines at the gym, and eating “pretty” healthy. Follow the guidelines above, and see what happens first.
14. Volek JS, Volk BM, Gómez AL, Kunces LJ, Kupchak BR, Freidenreich DJ, Aristizabal JC, Saenz C, Dunn-Lewis C, Ballard KD, Quann EE, Kawiecki DL, Flanagan SD, Comstock BA, Fragala MS, Earp JE, Fernandez ML, Bruno RS, Ptolemy AS, Kellogg MD, Maresh CM, Kraemer WJ. Whey protein supplementation during resistance training augments lean body mass. J Am Coll Nutr. 2013;32(2):122-35. PMID: 24015719
The changes in average serum testosterone levels with aging mean that the proportion of men fulfilling a biochemically defined diagnosis of hypogonadism increases with aging. Twenty percent of men aged over 60 have total testosterone levels below the normal range and the figure rises to 50% in those aged over 80. The figures concerning free testosterone are even higher as would be expected in view of the concurrent decrease in SHBG levels (Harman et al 2001).
In fact, testosterone supplements might cause more problems than they solve. Studies have suggested a connection between supplements and heart problems. A 2010 study reported in The New England Journal of Medicine showed that some men over age 65 had an increase in heart problems when they used testosterone gel. A later of men younger than 65 at risk for heart problems and heart-healthy older men showed that both groups had a greater risk of heart attack when taking testosterone supplements.
Zinc is little more of a nice-to-have ingredient than a must-have. It’s on our radar as an ingredient that possibly boosts testosterone levels, and while we couldn’t find enough supporting evidence that taking zinc would increase natural testosterone, low zinc levels have been connected to infertility. A low zinc level is also possibly a sign of hypogonadism. The closest support we found is in a study which found that people recovered from nutritional deficiency-related problems more quickly if they took a zinc supplement than those who did not. Zinc is available in many foods, such as oysters, fortified breakfast cereals, and red meat.
With the exception of increasing my fat and cholesterol intake, my diet wasn’t that unconventional. I didn’t follow a strictly low-carb or Paleo diet because recent research has suggested that a diet high in protein and low in carbs actually causes T levels to decrease. With that said, I was judicious with the carbs. I tried to get most of my carbs from veggies and fruit, but I didn’t freak out if my wife made us spaghetti for dinner.
The reason I started the experiment at that point is because I know a lot of guys who live my last-August lifestyle all the time, and I wanted to see what would happen to an “average” guy who turned things around. At the same time, there was no “normal” time in my life which would have been better for me to start the experiment. My stress level and diet fluctuates throughout the year anyway, so at any point, factors in my current lifestyle would have influenced the results. I wanted to begin at “ground zero.”
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)".[180] 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.[181][182]
Dr. Anthony's Notes: Creatine is damn effective. Period. It's research proven to benefit testosterone, energy levels, muscle preservation, and your brain function. Although creatine can be found naturally in a good high-protein diet, taking 5g daily is a great idea for most guys – especially those over 35. Remember to take your creatine AWAY from caffeine – the two substances inhibit each other's absorption. Verdict: this is one of the natural testosterone supplements that work. Best Food Sources: wild game (including venison, elk, buffalo, and bison), grass-fed beef, organic chicken, organic turkey, and wild-caught fish. How To Take Creatine Monohydrate: 5g daily away from caffeine.
Early infancy androgen effects are the least understood. In the first weeks of life for male infants, testosterone levels rise. The levels remain in a pubertal range for a few months, but usually reach the barely detectable levels of childhood by 4–7 months of age.[15][16] The function of this rise in humans is unknown. It has been theorized that brain masculinization is occurring since no significant changes have been identified in other parts of the body.[17] The male brain is masculinized by the aromatization of testosterone into estrogen, which crosses the blood–brain barrier and enters the male brain, whereas female fetuses have α-fetoprotein, which binds the estrogen so that female brains are not affected.[18]

High intensity exercise is crucial to boost testosterone (13).  Exercises should be explosive in nature and maximize the resistant overload on the muscles.  Large muscle group compound lifts such as squats, deadlifts & burpees are some of the best testosterone boosting exercises.  The training session should be short (5-30 mins) and have very little rest periods between sets.
Nutritional developers formulated Nugenix® with Testofen®, a key natural ingredient to help boost “free” testosterone along with resistance training. This key ingredient is carefully extracted from the fenugreek plant. A Testofen® study in Irvine, California indicated positive free testosterone-related results. Nugenix also includes L-Citrulline Malate, Tribulus, Zinc, plus Vitamins B6 and B12 to help promote overall health and performance.*

Dr. Anthony’s Notes: Magnesium is best to take at night as it is relaxing. Supplemental magnesium can cause loose stools at high doses. If you experience loose stools, you'll know to back off your dose. This is a really useful supplement for overall health – not JUST for testosterone. Verdict: this is one of the natural testosterone supplements that work. Best Food Sources: pumpkin seeds, spinach, swiss chard, black beans, cashews, quinoa, quality whole gains like Ezekiel bread How To Take Magnesium: 200-400mg capsule form at night before bed.

There are several supplements on the market claiming to be natural testosterone boosters. I get these sorts of things in the mail all time. The companies that produce these products claim that the herbs (typically stinging nettle and tribulus) in their pills increase free testosterone by reducing SHBG. They also throw in some B vitamins for “increased energy and vitality.”
There are supplements out there that promise to increase your libido while also upping your testosterone. There are over the counter testosterone supplements and prescription supplements. There are supplements that market themselves as T-boosters, while also touting themselves as an aphrodisiac. And then there are companies that claim to have developed a testosterone pill that contains the triumvirate of male-enhancing properties: T-boosting, libido-enhancing, and even fertility-increasing. These supplement makers sometimes throw in an additional claim of muscle gain as well.
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.
Another effect that can limit treatment is polycythemia, which occurs due to various stimulatory effects of testosterone on erythropoiesis (Zitzmann and Nieschlag 2004). Polycythemia is known to produce increased rates of cerebral ischemia and there have been reports of stroke during testosterone induced polycythaemia (Krauss et al 1991). It is necessary to monitor hematocrit during testosterone treatment, and hematocrit greater than 50% should prompt either a reduction of dose if testosterone levels are high or high-normal, or cessation of treatment if levels are low-normal. On the other hand, late onset hypogonadism frequently results in anemia which will then normalize during physiological testosterone replacement.
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The same study showed that drinking did, however, lower semen count and quality. And I want to remind you – this is an article  on improving testosterone levels, not general health as there are a lot of studies that show drinking leads to an assortment of health issues. This acute spike in Testosterone could be due to the effect alcohol has on libido, and also the energy influx in the liver?

Recently, a panel with cooperation from international andrology and urology societies, published specific recommendations with regard to the diagnosis of Late-onset Hypogonadism (Nieschlag et al 2005). These are summarized in the following text. It is advised that at least two serum testosterone measurements, taken before 11 am on different mornings, are necessary to confirm the diagnosis. The second sample should also include measurement of gonadotrophin and prolactin levels, which may indicate the need for further investigations for pituitary disease. Patients with serum total testosterone consistently below 8 nmol/l invariably demonstrate the clinical syndrome of hypogonadism and are likely to benefit from treatment. Patients with serum total testosterone in the range 8–12 nmol/l often have symptoms attributable to hypogonadism and it may be decided to offer either a clinical trial of testosterone treatment or to make further efforts to define serum bioavailable or free testosterone and then reconsider treatment. Patients with serum total testosterone persistently above 12 nmol/l do not have hypogonadism and symptoms are likely to be due to other disease states or ageing per se so testosterone treatment is not indicated.
Stored food in glassware and never, ever, ever heated food in plastic containers. Most modern plastics contain phthalates. Phthalates are what give plastic their flexibility, durability, and longevity. But they also screw with hormones by imitating estrogen. Because I didn’t want any of those T-draining molecules in my food, I kept all my food in glassware. I also made sure to never heat food in plastic containers, as heat increases the transfer of phthalates into food.
When testosterone and endorphins in ejaculated semen meet the cervical wall after sexual intercourse, females receive a spike in testosterone, endorphin, and oxytocin levels, and males after orgasm during copulation experience an increase in endorphins and a marked increase in oxytocin levels. This adds to the hospitable physiological environment in the female internal reproductive tract for conceiving, and later for nurturing the conceptus in the pre-embryonic stages, and stimulates feelings of love, desire, and paternal care in the male (this is the only time male oxytocin levels rival a female's).[citation needed]
Travison, T. G., Vesper, H. W., Orwoll, E, Wu, F., Kaufman, J. M., Wang, Y., …Bhasin, S. (2017, April1). Harmonized reference ranges for circulating testosterone levels in men of four cohort studies in the United States and Europe. The Journal of Clinical Endocrinology & Metabolism, 102(4), 1161–1173. Retrieved from https://academic.oup.com/jcem/article/102/4/1161/2884621

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.
Puberty occurs when there is an “awakening” of the hypothalamic-pituitary axis. The hypothalamus increases its secretion of gonadotropin releasing hormone (GnRH) which in turn stimulates the release of luteinizing hormone (LH) and follicle stimulating hormone (FSH). This leads to a significant increase in the production of testicular testosterone and the induction of the well-known secondary sex characteristics associated with puberty: growth spurt, increased libido, increased erectile function, acne, increased body hair, increased muscle mass, deepening of the voice, spermatogenesis, gynecomastia (usually transient).
Like most supplements, Beast Sports contains several ingredients with little research about their long-term effects. WebMD describes Suma powder, Rhodiola Rosea, Cissus quadrangularis, Tribulus extract, and ashwagandha extract as possibly safe when taken for a short period of time (usually around 6-10 weeks). However, their long-term safety remains unknown. It also has a few ingredients, like cyanotis vaga root, safed musli, and polygonum cispidatum root extract for which there is a lack of data on even short term safety.
Other Potential risks that can be caused by use of testosterone supplements are: People who take good testosterone supplements or any other kind of testosterone boosters can also experience many other side effects, including stomachache, problems with urination, dizziness, mood changes, intermittent breathing during sleep, changes in testicles, appetite loss, inflammation of gums, weight gain, nausea, painful erection, and protracted erection.
Men who produce more testosterone are more likely to engage in extramarital sex.[55] Testosterone levels do not rely on physical presence of a partner; testosterone levels of men engaging in same-city and long-distance relationships are similar.[54] Physical presence may be required for women who are in relationships for the testosterone–partner interaction, where same-city partnered women have lower testosterone levels than long-distance partnered women.[59]
There is increasing interest in the group of patients who fail to respond to treatment with PDE-5 inhibitors and have low serum testosterone levels. Evidence from placebo-controlled trials in this group of men shows that testosterone treatment added to PDE-5 inhibitors improves erectile function compared to PDE-5 inhibitors alone (Aversa et al 2003; Shabsigh et al 2004).
Testosterone retains nitrogen and is an essential ingredient in the development and maintenance of muscle mass (Sinha-Hikim et al 2006). With a diminution in testosterone, muscle mass diminishes as does strength. Weakness and fatigue result. A number of studies have demonstrated the ability of testosterone to restore lean body mass (muscle) in hypogonadal men, while at the same time causing a reduction in fat mass (Wang et al 2004). Treatment of hypogonadal men with testosterone results in improvement in overall physical performance as well as strength as assessed by, eg, hand grip power (Page 2005). Because of decreased muscle strength and impaired balance, older hypogonadal men are susceptible to falling and since they may already be osteopenic or osteoporotic as a consequence of hypogonadism, they are at increased risk for fracture as a result of the fall (Szulc et al 2003). Men with low levels of testosterone as in androgen deprivation therapy for prostate cancer, have a significant decrease in lean body mass and hemoglobin, while at the same time they experience an increase in weight, body fat and body mass index (Smith et al 2002). Treatment of frail hypogonadal men with testosterone, therefore, can result in changes in muscle gene expression, increased muscle mass, improvements in strength, power and endurance and improved physical function.

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).
A: According to the NIH, normal values for testosterone levels in men can range from 300 to 1,200ng/dL. There can be many different causes of low testosterone including age, diseases, accidents, and medications. Symptoms of low testosterone may include: loss of sex drive, erectile dysfunction, depressed mood, and difficulty concentrating. Low testosterone levels may also bring around body changes including: hair loss, decrease in blood cells possibly leading to anemia, fragile bones, and a decrease in muscle mass. There are different testosterone replacement therapies including patches, such as Androderm; gels, such as Androgel and Testim; and injections, such as testosterone cypionate. Only your health care provider can decide if and what kind of testosterone replacement therapy is appropriate for you. Testosterone replacement therapy is not right for everyone. Patient with certain prostate issues or breast cancer should not take testosterone. For more specific information, consult with your doctor for guidance based on your health status and current medications, particularly before taking any action. Kristen Dore, PharmD

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.
If you want to naturally boost testosterone and HGH then combining weight training with HIIT workouts (high intensity interval training). Go to the gym at least three days a week, ideally at least three days a week, and lift heavy weights. Lifting heavy weights 6–12 reps with larger muscle groups like your quadriceps, hamstrings, back, shoulders and chest will help your body pack on the maximum amount of muscle. Specifically, lifting at least 30 minutes up to as long as an hour or so can be very, very beneficial boost low testosterone levels.
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 an anabolic steroid hormone that plays a critical role in metabolism, sex drive, muscle building, mood regulation, memory & cognitive function.  Normal testosterone levels play a huge role in maintaining optimal weight as well as reducing risk of degenerative diseases such as osteoporosis, heart disease, diabetes, & certain cancers (1, 2, 3).
Miscellaneous: Sleep: (REM sleep) increases nocturnal testosterone levels.[142] Behavior: Dominance challenges can, in some cases, stimulate increased testosterone release in men.[143] Drugs: Natural or man-made antiandrogens including spearmint tea reduce testosterone levels.[144][145][146] Licorice can decrease the production of testosterone and this effect is greater in females.[147]
Common side effects from testosterone medication include acne, swelling, and breast enlargement in males.[10] Serious side effects may include liver toxicity, heart disease, and behavioral changes.[10] Women and children who are exposed may develop virilization.[10] It is recommended that individuals with prostate cancer not use the medication.[10] It can cause harm if used during pregnancy or breastfeeding.[10]
As already indicated previously, testosterone levels, particularly bioavailable testosterone, fall with advancing age. This decline in testosterone availability may start to occur early in the forth decade but it usually becomes clinically manifest in the 50s and 60s. Although there is continuing debate about the best way to diagnose hypogonadism in the aging male, there appears to be a general consensus that symptomatic men with reduced levels of testosterone should be given a trial of testosterone therapy if there is no contraindication to do so (Bain et al 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.