Looking purely at the biochemical numbers, The Endocrine Society* considers low testosterone to be a total testosterone level of less than 300 ng/dl, and I think that’s a reasonable guide. But no one quite agrees on a number. It’s not like diabetes, where if your fasting glucose is above a certain level, they’ll say, “Okay, you’ve got it.” With testosterone, that break point is not quite as clear.
The mechanism of age related decreases in serum testosterone levels has also been the subject of investigation. Metabolic clearance declines with age but this effect is less pronounced than a reduction in testosterone production, so the overall effect is to reduce serum testosterone levels. Gonadotrophin levels rise during aging (Feldman et al 2002) and testicular secretory responses to recombinant human chorionic gonadotrophin (hCG) are reduced (Mulligan et al 1999, 2001). This implies that the reduced production may be caused by primary testicular failure but in fact these changes are not adequate to fully explain the fall in testosterone levels. There are changes in the lutenising hormone (LH) production which consist of decreased LH pulse frequency and amplitude, (Veldhuis et al 1992; Pincus et al 1997) although pituitary production of LH in response to pharmacological stimulation with exogenous GnRH analogues is preserved (Mulligan et al 1999). It therefore seems likely that there are changes in endogenous production of GnRH which underlie the changes in LH secretion and have a role in the age related decline in testosterone. Thus the decreases in testosterone levels with aging seem to reflect changes at all levels of the hypothalamic-pituitary-testicular axis. With advancing age there is also a reduction in androgen receptor concentration in some target tissues and this may contribute to the clinical syndrome of LOH (Ono et al 1988; Gallon et al 1989).
The participants were seen every 4 weeks. Blood was taken to measure hormone levels, and questionnaires were given to assess physical function, health status, vitality, and sexual function. Body fat and muscle measurements were also taken at the beginning and end of the 16 weeks. The study was funded in part by NIH’s National Institute on Aging (NIA) and National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Results appeared in the September 12, 2013, issue of the New England Journal of Medicine.

Elevated testosterone levels have been demonstrated to increase the growth of body muscles and contribute to better activation of the nervous system, resulting in more power and strength, a better mood, enhanced libido, and many other benefits.[3] Previous researches done on the anabolic role of testosterone and its impact on muscular strength in training-induced adaptations has provided rather conflicting findings, and a positive correlation between testosterone-mediated responses and both functional performance and body composition was found.[4,5] There are a number of naturally occurring substances that can boost testosterone levels in the body. Foods containing such substances are known as testosterone-foods; and they tend to be rich in vitamins, antioxidants, and minerals like zinc, which plays a key role in testosterone production.[2,6-8]

Hello everyone. First off, thank you Dr. Abraham Morgentaler, for the excellent and refreshing article. I do not intend to spill my guts about symptoms or values on here as it has already been done so many times over. I will say that I am an RN BSN and have been on HRT for going on 6 yrs. I live in Oklahoma and when I first started noticing symptoms I knew something was wrong and began to do research myself. With an initial level of 241 no doctor here at that time, would even consider HRT as I was only 35ish at the time.
Lets touch on these individually. Gluten has been shown to increase prolactin levels in male mice (48 & 49). Increased prolactin levels in males leads to all sorts of horrible things: Man Boobs (50), High inflammation (51), and most importantly, higher prolactin levels have been shown to be testosterone lowering and lead to shrinking of the testicle (52).

For facts sake I am 51yr old male and I am fat. I do have a large and muscular fat, but I also have a good amount of at on top of that. My body shape is not the typical huge “beer belly” gut that is hard and dangerous, rather, I am fat all over proportionally, but still considered obese. The fat on my body and around my middle is quite soft compared to male friends who have those large and hard bellies. Still, my doctor and reading indicate that fat has an effect on T potentially lowering the overall level that my T would be if I lost a good amount of that fat.
While steroids like DHEA can be used to boost testosterone, if used in the wrong dosages or by people who don’t need them they can raise T-levels far beyond the normal range, which is what causes accelerated muscle gain. According to Dr. Emil Hodzovic, who is a competitive bodybuilder as well as a doctor with Medichecks, steroids come with “a set of risks, including liver damage, hormone imbalance, high blood pressure, and a higher risk of a stroke or heart attack”.
If you have low testosterone and are prescribed testosterone therapy by your doctor, it does not increase your risk for getting prostate cancer. However, in some patients with existing prostate cancer, adding testosterone hormone therapy can make the cancer grow faster. Men with low testosterone levels are actually more likely to get prostate cancer than men with normal prostate levels. You need to discuss these details with your physician and make the best decision for you.
Trials of testosterone treatment in men with type 2 diabetes have also taken place. A recent randomized controlled crossover trial assessed the effects of intramuscular testosterone replacement to achieve levels within the physiological range, compared with placebo injections in 24 men with diabetes, hypogonadism and a mean age of 64 years (Kapoor et al 2006). Ten of these men were insulin treated. Testosterone treatment led to a significant reduction in glycated hemoglobin (HbA1C) and fasting glucose compared to placebo. Testosterone also produced a significant reduction in insulin resistance, measured by the homeostatic model assessment (HOMA), in the fourteen non-insulin treated patients. It is not possible to measure insulin resistance in patients treated with insulin but five out of ten of these patients had a reduction of insulin dose during the study. Other significant changes during testosterone treatment in this trial were reduced total cholesterol, waist circumference and waist-hip ratio. Similarly, a placebo-controlled but non-blinded trial in 24 men with visceral obesity, diabetes, hypogonadism and mean age 57 years found that three months of oral testosterone treatment led to significant reductions in HbA1C, fasting glucose, post-prandial glucose, weight, fat mass and waist-hip ratio (Boyanov et al 2003). In contrast, an uncontrolled study of 150 mg intramuscular testosterone given to 10 patients, average age 64 years, with diabetes and hypogonadism found no significant change in diabetes control, fasting glucose or insulin levels (Corrales et al 2004). Another uncontrolled study showed no beneficial effect of testosterone treatment on insulin resistance, measured by HOMA and ‘minimal model’ of area under acute insulin response curves, in 11 patients with type 2 diabetes aged between 33 and 73 years (Lee et al 2005). Body mass index was within the normal range in this population and there was no change in waist-hip ratio or weight during testosterone treatment. Baseline testosterone levels were in the low-normal range and patients received a relatively small dose of 100 mg intramuscular testosterone every three weeks. A good increase in testosterone levels during the trial is described but it is not stated at which time during the three week cycle the testosterone levels were tested, so the lack of response could reflect an insufficient overall testosterone dose in the trial period.
There’s a significant failure rate of the PDE5 inhibitors for erectile dysfunction, something on the order of 25% to 50%, depending on the underlying condition. It turns out that a third of those men will have adequate erections with testosterone-replacement therapy alone and another third will have adequate erections with the pills and testosterone combined. There’s still a third who don’t respond, but normalizing their testosterone level has definitely rescued many men who had failed on PDE5 inhibitors.
The prevalence of biochemical testosterone deficiency increases with age. This is partly due to decreasing testosterone levels associated with illness or debility but there is also convincing epidemiological data to show that serum free and total testosterone levels also fall with normal aging (Harman et al 2001; Feldman et al 2002). The symptoms of aging include tiredness, lack of energy, reduced strength, frailty, loss of libido, decreased sexual performance depression and mood change. Men with hypogonadism experience similar symptoms. This raises the question of whether some symptoms of aging could be due to relative androgen deficiency. On the other hand, similarities between normal aging and the symptoms of mild androgen deficiency make the clinical diagnosis of hypogonadism in aging men more challenging.
Another recent development is the production of adhesive tablets which are applied twice daily to the buccal mucosa on the gum above the incisor teeth. The tablets gradually release testosterone into the systemic venous circulation and steady state physiological concentrations are achieved in most patients within two days (Ross et al 2004). Some patients do not like the feeling of the tablet in the mouth or find that there is an abnormal taste in the mouth, but local adverse effects are usually mild and transient (Wang, Swerdloff et al 2004).
A recent study compared total and bioavailable testosterone levels with inflammatory cytokines in men aged 65 and over. There was an inverse correlation with the pro-inflammatory soluble interleukin-6 receptor, but no association with interleukin-6 (IL-6), highly sensitive CRP (hsCRP), tumor necrosis factor-α (TNF-α) or interleukin-1β (IL-1β (Maggio et al 2006). Another trial found that young men with idiopathic hypogonadotrophic hypogonadism had higher levels of proinflammatory factors interleukin-2 (IL-2), interleukin-4 (IL-4), complement C3c and total immunoglobulin in comparison to controls (Yesilova et al 2000). Testosterone treatment in a group of hypogonadal men, mostly with known coronary artery disease, induced anti-inflammatory changes in the cytokine profile of reduced IL-1β and TNF-α and increased IL-10 (Malkin, Pugh, Jones et al 2004).
I started doing prostate biopsies before putting men on testosterone therapy because the fear had always been that a hidden cancer might grow due to increased testosterone. It was also believed that low testosterone was protective. Well, we found prostate cancer in one of the first men with low testosterone we biopsied, even though his PSA level and digital rectal exam (DRE) were normal. As we did more of these, we found more and more cases, about one out of seven, despite normal DRE and normal PSA. When we had data for 77 men and the cancer rate was about the same, 14%, the Journal of the American Medical Association published our findings. At the time, that rate of prostate cancer in men with normal PSA was several times higher than anything published previously, and it approximated the risk of men who had an elevated PSA or an abnormal DRE. That was in 1996.
Garlic is a very effective food that has been used for centuries in treating various physical ailments including heart problems and respiratory infections. What most people don’t know is that it is also a potent aphrodisiac and very effective in boosting sperm volume. It contains a compound called allicin which improves blood flow to the male sexual organs, increasing sperm production and semen volume.
Men can experience a range of symptoms if testosterone decreases more than it should. Low testosterone, or low T, is diagnosed when levels fall below 300 nanograms per deciliter (ng/dL). A normal range is typically 300–1000 ng/dL, according to the U.S. Food and Drug Administration. A blood test called a serum testosterone test is used to determine your level of circulating testosterone.

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.”
The general recommendation is that men 50 and older who are candidates for testosterone therapy should have a DRE and a PSA test. If either is abnormal, the man should be evaluated further for prostate cancer, which is what we do with everybody whether they have low testosterone or not. That means a biopsy. But if all of those results are normal, then we can initiate testosterone therapy. The monitoring that needs to happen for men who begin testosterone therapy is really very simple: DRE, PSA, and a blood test for hematocrit or hemoglobin, once or twice in the first year and then yearly after that, which is pretty much what we recommend for most men over age 50 anyway.
It doesn’t get more natural than getting a good night’s sleep. Research published in the Journal of the American Medical Association showed that lack of sleep can greatly reduce a healthy young man’s testosterone levels. That effect is clear after only one week of reduced sleep. Testosterone levels were particularly low between 2 and 10 p.m. on sleep-restricted days. Study participants also reported a decreased sense of wellbeing as their blood testosterone levels dropped.
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.*
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.

We also have epidemiologic studies, like the Physicians’ Health Study, the Baltimore Longitudinal Study of Aging, and the Massachusetts Male Aging Study, that include tens of thousands of men who are followed for 5, 10, 15, or even 20 years. At the end of the study period, the researchers see who developed prostate cancer and who didn’t. They can then look at blood samples taken at the start of the study to see if, for example, the group that got prostate cancer had a higher level of testosterone over all. About 500,000 men have been entered in some 20 trials of this type around the world. Not one of those studies has shown a definitive correlation between prostate cancer and total testosterone. Three or four have shown weak associations, but none of those have been confirmed in subsequent studies.


ALABAMA - ALASKA - ARIZONA - ARKANSAS - CALIFORNIA - COLORADO - CONNECTICUT - DELAWARE - FLORIDA - GEORGIA - HAWAII - IDAHO - ILLINOIS - INDIANA - IOWA - KANSAS - KENTUCKY - LOUISIANA - MAINE - MARYLAND - MASSACHUSETTS - MICHIGAN - MINNESOTA - MISSISSIPPI - MONTANA - NEBRASKA - NEW HAMPSHIRE - NEW YORK - NEW JERSEY - NEW MEXICO - NEVADA - NORTH CAROLINA - NORTH DAKOTA - OHIO - OKLAHOMA - OREGON - PENNSYLVANIA - RHODE ISLAND - SOUTH CAROLINA - SOUTH DAKOTA - TENNESSEE - TEXAS - UTAH - VERMONT - VIRGINIA - WASHINGTON - WASHINGTON DC - WEST VIRGINIA - WISCONSIN - WYOMING

For facts sake I am 51yr old male and I am fat. I do have a large and muscular fat, but I also have a good amount of at on top of that. My body shape is not the typical huge “beer belly” gut that is hard and dangerous, rather, I am fat all over proportionally, but still considered obese. The fat on my body and around my middle is quite soft compared to male friends who have those large and hard bellies. Still, my doctor and reading indicate that fat has an effect on T potentially lowering the overall level that my T would be if I lost a good amount of that fat.
Most men report being able to lose body fat and gain lean muscle more easily when they take testosterone boosters. These supplements can also raise a man’s mood and make him feel more confident. You might notice that your libido gets a boost, too. They make workouts more effective and, in some cases, easier. Testosterone boosters are also great for men with low testosterone levels, as they will combat the low energy and fatigue that go along with low levels. Other supplements to consider are energy-boosting supplements and pre-workout supplements.
^ Butenandt A, Hanisch G (1935). "Umwandlung des Dehydroandrosterons in Androstendiol und Testosterone; ein Weg zur Darstellung des Testosterons aus Cholestrin" [About Testosterone. Conversion of Dehydro-androsterons into androstendiol and testosterone; a way for the structure assignment of testosterone from cholesterol]. Hoppe-Seyler's Z Physiol Chem (in German). 237 (2): 89–97. doi:10.1515/bchm2.1935.237.1-3.89.
Let me start out by saying that I didn't notice anything for about the first 10 days. After week 2, I had moderate energy increases buy by far the most noticeable difference for me was in the bedroom. After using this product for over a moth now, I normally run out of energy before I run out of "stamina". This will be a permanent regimen for my daily supplements from now on. I take 4 a day. 2 in the morning and 2 about 5pm. I thought about lowering the dosage to see if it had the same effect, but for the price, why? LOL.
On the average, you need to sleep at least 8 hours per night to stay healthy. If you want a night sleep to contribute to the maximum testosterone production, it’s important to make your sleep comfortable. Thus, the bedroom temperature shouldn’t exceed 21°C. In addition, you should ventilate your bedroom thoroughly before sleeping. Furthermore, before going to bed, don’t overload your stomach with fatty foods, as well as don’t drink alcohol and caffeinated beverages. Finally, you have to avoid intense physical activity before bedtime.6
In fact, high cortisol deals a crushing blow to testosterone in two ways. During, long-lasting stress, high amounts of cortisol release very often and have a direct negative influence on T levels. Thus, cortisol inhibits testosterone synthesis in the testes and hypothalamus. In addition, the production of cortisol is impossible without cholesterol. But testosterone synthesis also demands cholesterol. Since during stress cholesterol is first of all used for making cortisol, T levels simply plummet.
Sportsmen are permitted to use the boosters to trigger the mechanism of testosterone synthesis in the body. These products won a wide popularity among the sportsmen. The matter is that the supplements work by substantially enhancing sports performance, reviving strength, boosting endurance, coping with excessive stress levels, and decreasing time necessary for recovery after exhausting exercises.

The evidence shows that testosterone treatment does not change the strength or rate of urine flow, does not change the ability to empty the bladder, and does not change other symptoms such as frequency or urgency of urination, as assessed by the American Urological Association Symptom Score or the International Prostate Symptom Score. I’ve had a couple of patients over the years who had some worsening of urinary symptoms with testosterone, but that’s rare, even with long-term use.
I have been searching quite a while for a testosterone booster that could help me in a few different ways yet not to be too expensive. Over the years, I have experienced a low irritability tolerance(meaning it doesn’t take much to send me “over the top”) and have moods swings due to negative situations. I would like to be more at peace with myself & around others(without trying to fake it).I don’t usually have a lot of energy at work & rely on energy drinks. I also have a lower sex drive due to what I believe is low blood flow. I am 43 years old and am not over weight, but could stand to tone up and lose a little around the waist. If this site is legit, I would like to know your opinion on what I have disclosed & what you recommend.
Remember that each person is unique, and each body responds differently to treatment. TT may help erectile function, low sex drive, bone marrow density, anemia, lean body mass, and/or symptoms of depression. However, there is no strong evidence that TT will help memory recall, measures of diabetes, energy, tiredness, lipid profiles, or quality of life.
During the second trimester, androgen level is associated with sex formation.[13] This period affects the femininization or masculinization of the fetus and can be a better predictor of feminine or masculine behaviours such as sex typed behaviour than an adult's own levels. A mother's testosterone level during pregnancy is correlated with her daughter's sex-typical behavior as an adult, and the correlation is even stronger than with the daughter's own adult testosterone level.[14]
Overall there is evidence that testosterone treatment increases lean body mass and reduces obesity, particularly visceral obesity, in a variety of populations including aging men. With regard to muscle changes, some studies demonstrate improvements in maximal strength but the results are inconsistent and it has not been demonstrated that these changes lead to clinically important improvements in mobility, endurance or quality of life. Studies are needed to clarify this. Changes in abdominal obesity are particularly important as visceral fat is now recognised as predisposing the metabolic syndrome, diabetes and cardiovascular disease.

I am still on T therapy. But here’s what pisses me off: No one tells you that you will be hooked on the drug virtually forever! Don’t ever stop it abruptly! I did and I had a major crash: physically and emotionally. I went into the darkest depression ever…and I was lacking in energy so much that I had to have 4 naps a day…just to get through the day. I was also robbed of any initiative to do anything.
Spinach/Spring Salad Mix. This was the base of my salad. I used Organic Girl Greens from Whole Foods. Yeah, I know. The base of my Man Salad came from a company called Organic Girl. Spinach and other leafy green vegetables contain minerals like magnesium and zinc, which have been shown to aid in testosterone production (study on magnesium, and another; study on zinc)
ALABAMA - ALASKA - ARIZONA - ARKANSAS - CALIFORNIA - COLORADO - CONNECTICUT - DELAWARE - FLORIDA - GEORGIA - HAWAII - IDAHO - ILLINOIS - INDIANA - IOWA - KANSAS - KENTUCKY - LOUISIANA - MAINE - MARYLAND - MASSACHUSETTS - MICHIGAN - MINNESOTA - MISSISSIPPI - MONTANA - NEBRASKA - NEW HAMPSHIRE - NEW YORK - NEW JERSEY - NEW MEXICO - NEVADA - NORTH CAROLINA - NORTH DAKOTA - OHIO - OKLAHOMA - OREGON - PENNSYLVANIA - RHODE ISLAND - SOUTH CAROLINA - SOUTH DAKOTA - TENNESSEE - TEXAS - UTAH - VERMONT - VIRGINIA - WASHINGTON - WASHINGTON DC - WEST VIRGINIA - WISCONSIN - WYOMING
46 year old whose suffered with low libido and all the related symptoms for over a decade. Finally had the courage to have a frank talk with dr. and urologist. Testosterone level 165, free testos level 3.6. Re-doing blood work again just to be sure in the next week or so, and will post updates then as things progress. Normal ranges are 300-1200 and 6 to 12.
^ Mehta PH, Jones AC, Josephs RA (Jun 2008). "The social endocrinology of dominance: basal testosterone predicts cortisol changes and behavior following victory and defeat" (PDF). Journal of Personality and Social Psychology. 94 (6): 1078–93. CiteSeerX 10.1.1.336.2502. doi:10.1037/0022-3514.94.6.1078. PMID 18505319. Archived from the original (PDF) on April 19, 2009.
In my late 40’s I was on Androgel. I lost weight and gained muscle; became healthier over all, brighter outlook, more active, and a harder erection that had a mind of it’s own. Then I went on injectable testosterone. My numbers are normal but my weight is up even after eating less. As well everything else is shelter smelter. I intend to get back to Androgel. (this, of course, is my own personal study)
Cross-sectional studies conducted at the time of diagnosis of BPH have failed to show consistent differences in testosterone levels between patients and controls. A prospective study also failed to demonstrate a correlation between testosterone and the development of BPH (Gann et al 1995). Clinical trials have shown that testosterone treatment of hypogonadal men does cause growth of the prostate, but only to the size seen in normal men, and also causes a small increase in prostate specific antigen (PSA) within the normal range (Rhoden and Morgentaler 2005). Despite growth of the prostate a number of studies have failed to detect any adverse effects on symptoms of urinary obstruction or physiological measurements such as flow rates and residual volumes (Snyder et al 1999; Kenny et al 2000, 2001). Despite the lack of evidence linking symptoms of BPH to testosterone treatment, it remains important to monitor for any new or deteriorating problems when commencing patients on testosterone treatment, as the small growth of prostate tissue may adversely affect a certain subset of individuals.
Popular through the centuries in Ayurvedic healing (a traditional practice of medicine in India) ashwagandha is what is known as an "adaptogen." This means the body may be able to use it to help adapt to stressors. While many people supplement with it for reducing cortisol, anxiety, and fatigue levels, ashwagandha also holds relevance for us here with potential testosterone boosting benefits.[8]
To get your levels into the healthy range, sun exposure is the BEST way to optimize your vitamin D levels; exposing a large amount of your skin until it turns the lightest shade of pink, as near to solar noon as possible, is typically necessary to achieve adequate vitamin D production. If sun exposure is not an option, a safe tanning bed (with electronic ballasts rather than magnetic ballasts, to avoid unnecessary exposure to EMF fields) can be used.
There is a polymorphic CAG repeat sequence in the androgen receptor gene, which codes for a variable number of glutamine amino acids in the part of the receptor affecting gene transcription. A receptor with a short CAG sequence produces greater activity when androgens attach, and men with shorter CAG polymorphisms exhibit androgenic traits, such as preserved bone density (Zitzmann et al 2001) and prostate growth during testosterone treatment (Zitzmann et al 2003). Indirect evidence of the importance of androgens in the development of prostate cancer is provided by case control study findings of a shorter, more active CAG repeat sequence in the androgen receptor gene of patients with prostate cancer compared with controls (Hsing et al 2000, 2002).
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When I was on 4 pumps per day, I had a reduction of ejaculate, and sometimes found it hard to ejaculate. Getting erections is no problem, and I even take BP meds. I vary it now. When I’m not going to the gym, or traveling, I cut down to 2 pumps, or take a break for a few days. When I’m intense in the gym, I stick with 4 pumps (about 5mg). I do still have the belly flab unfortunately. I need to increase cardio, and change up the diet some, but honestly, I am not too bad with my diet, so I’m a little frustrated.
Longitudinal studies in male aging studies have shown that serum testosterone levels decline with age (Harman et al 2001; Feldman et al 2002). Total testosterone levels fall at an average of 1.6% per year whilst free and bioavailable levels fall by 2%–3% per year. The reduction in free and bioavailable testosterone levels is larger because aging is also associated with increases in SHBG levels (Feldman et al 2002). Cross-sectional data supports these trends but has usually shown smaller reductions in testosterone levels with aging (Feldman et al 2002). This is likely to reflect strict entry criteria to cross-sectional studies so that young healthy men are compared to older healthy men. During the course of longitudinal studies some men may develop pathologies which accentuate decreases in testosterone levels.
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