Changes in body composition are seen with aging. In general terms, aging males are prone to loss of muscle mass and a gain in fat mass, especially in the form of visceral or central fat. An epidemiological study of community dwelling men aged between 24 and 85 years has confirmed that total and free testosterone levels are inversely correlated with waist circumference and that testosterone levels are specifically related to this measure of central obesity rather than general obesity (Svartberg, von Muhlen, Sundsfjord et al 2004). Prospective studies show that testosterone levels predict future development of central obesity (Khaw and Barrett-Connor 1992; Tsai et al 2000). Reductions in free testosterone also correlate with age related declines in fat free mass (muscle mass) and muscle strength (Baumgartner et al 1999; Roy et al 2002). Studies in hypogonadal men confirm an increase in fat mass and decrease in fat free mass versus comparable eugonadal men (Katznelson et al 1998). Taken together, the epidemiological data suggest that a hypogonadal state promotes loss of muscle mass and a gain in fat mass, particularly visceral fat and therefore mimics the changes of ‘normal’ aging.
Phthalates are found to cause poor testosterone synthesis by disrupting an enzyme required to create the male hormone. Women with high levels of DEHP and DBP (two types of phthalates) in their system during pregnancy were found to have sons that had feminine characteristics Phthalates are found in vinyl flooring, detergents, automotive plastics, soaps and shampoos, deodorants, perfumes, hair sprays, plastic bags and food packaging, among a long list of common products. Aside from phthalates, other chemicals that possess gender-bending traits are:
In general, the normal range in males is about 270 to 1070 ng/dL with an average level of 679 ng/dL. A normal male testosterone level peaks at about age 20, and then it slowly declines. Testosterone levels above or below the normal range are considered by many to be out of balance. Moreover, some researchers suggest that the healthiest men have testosterone levels between 400 - 600 ng/dL.

Reviews.com has an advertising relationship with some of the offers included on this page. However, the rankings and listings of our reviews, tools and all other content are based on objective analysis. For more information, please check out our full Advertiser Disclosure. Reviews.com strives to keep its information accurate and up to date. The information in our reviews could be different from what you find when visiting a financial institution, service provider or a specific product’s website. All products are presented without warranty.
Why the difference? The discrepancy in findings between these studies is likely due to the initial training status and base testosterone levels of the subjects. While more research is warranted on this ingredient, D-AA is one of several ingredients suggested to be effective in boosting test levels, especially for older men whose natural testosterone levels have declined due to the natural course of aging.
Caffeine. Use caffeine moderately. Too much of the jittery juice increases cortisol, which decreases testosterone. Moreover, consuming caffeine late in the day hurts sleep, which lowers testosterone production. But one recent study indicates that caffeine consumed before working out may boost testosterone levels and help you exercise more efficiently. During my experiment I popped a piece of caffeinated gum five minutes before my workouts. Each piece had 100 mg of caffeine, about the same amount in a cup of coffee. That was usually it for my caffeine intake that day.

Scientists in Italy found that subjects who consumed roughly 3 grams of D-AA for 12 days observed a 42 percent increase in testosterone levels.[12] The researchers also noted that the D-AA group still had 22 percent more testosterone than the placebo group three days after they stopped supplementing. Conversely, a more recent article published in Nutrition Research found no increase in testosterone levels in resistance-trained males after supplementing with 3 grams of D-AA for 28 days.[13]
"The Journal of Clinical Endocrinology and Metabolism" published that males who switched from a high-fat diet to a low-fat diet also saw a decrease in their testosterone levels. If you want to put some fat back into your diet without fearing cardiac implications, plant-based saturated fat like coconut is just the ticket. Meat-based fat is also acceptable if kept to less than 10% of your dietary fat intake.
We required all of our testosterone boosters to have magnesium, but gave preference to magnesium aspartate, citrate, lactate, and chloride. These forms have been found to be more easily absorbed than magnesium oxide and sulfate. (On the other hand, it didn’t count if the supplement had magnesium stearate, which is used to make pills not stick together.)
Binge drinking on the other hand does impact Testosterone levels – especially on a short term basis. Two studies (22 & 23) show that large acute quantities of alcohol consumption in a short period led to decreases in Testosterone levels by a whooping 20-23% after 24hours! Note however this is drinking to extreme excess! Likewise, chronic alcohol abuse is known to reduce testosterone more notably (as seen in alcoholics).
Your body’s circadian rhythm essentially resets itself every night and releases chemicals like cortisol, which contribute to the overall hormone balance that can prevent low T-levels. I have even heard one endocrinologist claim that one hour of sleep between 10 p.m. and 2 a.m. has the same healing effects on your body as two hours of sleep before or after this timeslot!

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.
A testicular action was linked to circulating blood fractions – now understood to be a family of androgenic hormones – in the early work on castration and testicular transplantation in fowl by Arnold Adolph Berthold (1803–1861).[177] Research on the action of testosterone received a brief boost in 1889, when the Harvard professor Charles-Édouard Brown-Séquard (1817–1894), then in Paris, self-injected subcutaneously a "rejuvenating elixir" consisting of an extract of dog and guinea pig testicle. He reported in The Lancet that his vigor and feeling of well-being were markedly restored but the effects were transient,[178] and Brown-Séquard's hopes for the compound were dashed. Suffering the ridicule of his colleagues, he abandoned his work on the mechanisms and effects of androgens in human beings.
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.
Present in much greater levels in men than women, testosterone initiates the development of the male internal and external reproductive organs during foetal development and is essential for the production of sperm in adult life. This hormone also signals the body to make new blood cells, ensures that muscles and bones stay strong during and after puberty and enhances libido both in men and women. Testosterone is linked to many of the changes seen in boys during puberty (including an increase in height, body and pubic hair growth, enlargement of the penis, testes and prostate gland, and changes in sexual and aggressive behaviour). It also regulates the secretion of luteinising hormone and follicle stimulating hormone. To effect these changes, testosterone is often converted into another androgen called dihydrotestosterone. 

A diagnosis of low testosterone is typically made if a man’s free testosterone hormone level is below 300 ng/dL. But as a doctor specializing in sexual health, I typically consider optimized male testosterone levels somewhere between 600 to 800 ng/dL—rarely above or below those numbers. The tests that I routinely recommend to my male clients can be found in this test panel and include biomarkers associated with testosterone, free and total (this includes sex-hormone binding globulin [SHBG]), estradiol, estrogen (total and serum), cortisol, DHEAs, thyroid-stimulating hormone (TSH), hemoglobin A1C, and vitamin D.
In compliance with the FTC guidelines, please assume the following about links and posts on this site: Many of the links on DrJockers.com are affiliate links of which I receive a small commission from sales of certain items, but the price is the same for you. If I post an affiliate link to a product, it is something that I personally use, support and would recommend without an affiliate link. Learn More
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.
If testosterone deficiency occurs during fetal development, then male characteristics may not completely develop. If testosterone deficiency occurs during puberty, a boy’s growth may slow and no growth spurt will be seen. The child may have reduced development of pubic hair, growth of the penis and testes, and deepening of the voice. Around the time of puberty, boys with too little testosterone may also have less than normal strength and endurance, and their arms and legs may continue to grow out of proportion with the rest of their body.
This summary is intended for general informational purposes only, and should not be interpreted as specific medical advice. The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of purity, strength, or safety of the products. As a result, effects may vary. You should read product labels. In addition, if you are taking medications, herbs, or other supplements you should consult with a qualified healthcare provider before taking a supplement as supplements may interact with other medications, herbs, and nutritional products. If you have a medical condition, including if you are pregnant or nursing, you should speak to your physician before taking a supplement. Consult a healthcare provider if you experience side effects.
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. 
×