The second theory is similar and is known as "evolutionary neuroandrogenic (ENA) theory of male aggression".[78][79] Testosterone and other androgens have evolved to masculinize a brain in order to be competitive even to the point of risking harm to the person and others. By doing so, individuals with masculinized brains as a result of pre-natal and adult life testosterone and androgens enhance their resource acquiring abilities in order to survive, attract and copulate with mates as much as possible.[78] The masculinization of the brain is not just mediated by testosterone levels at the adult stage, but also testosterone exposure in the womb as a fetus. Higher pre-natal testosterone indicated by a low digit ratio as well as adult testosterone levels increased risk of fouls or aggression among male players in a soccer game.[80] Studies have also found higher pre-natal testosterone or lower digit ratio to be correlated with higher aggression in males.[81][82][83][84][85]

There are valid concerns about the safety of long-term treatment with testosterone particularly with respect to the cardiovascular system and the potential for stimulating prostate cancer development. There are no convincing hard data, however, to support these concerns. If anything, the data strongly suggest that adequate testosterone availability is cardioprotective and coronary risk factors such as diabetes, obesity and the metabolic syndrome are associated with reduced testosterone levels. It is certainly appropriate to avoid giving testosterone to men with prostate or breast cancer but it is not appropriate to accuse testosterone of inducing the development of de novo prostate cancers since evidence for this accusation is lacking (Wang et al 2004; Feneley and Carruthers 2006).
Withania Somnifera is another name for Ashwagandha which is an ancient herb used as a medicine. It is an adaptogen because it helps the body to handle anxiety and stress. It improves T levels along with increasing sperm production. Other than improvement in sexual performance it also helps in fat loss, strength, and stamina. It reduces the stress by reducing the output of the cortisol hormone, which acts antagonist to testosterone. This reduction helps to body to trigger the testosterone production.
The natural production of DHEA is also age-dependent. Prior to puberty, the body produces very little DHEA. Production of this prohormone peaks during your late 20’s or early 30’s. With age, DHEA production begins to decline. The adrenal glands also manufacture the stress hormone cortisol, which is in direct competition with DHEA for production because they use the same hormonal substrate known as pregnenolone. Chronic stress basically causes excessive cortisol levels and impairs DHEA production, which is why stress is another factor for low testosterone levels.
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)
There are no studies showing its effects on healthy males, but it has been shown to drastically improve testosterone in infertile males (ref 77). It's also packed full of minerals, so is a great superfood nevertheless. I use the Sunfoods brand. Make sure you buy from a quality brand, as there are a lot of poor shilajit products out there, also some have been shown to be high in heavy metals. 

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The first period occurs between 4 and 6 weeks of the gestation. Examples include genital virilisation such as midline fusion, phallic urethra, scrotal thinning and rugation, and phallic enlargement; although the role of testosterone is far smaller than that of dihydrotestosterone. There is also development of the prostate gland and seminal vesicles.
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.
Let’s do a quick review of what I shared in the introduction to this series. August of last year was a tough month for me, primarily because of a huge and grueling project we were in the midst of here on the site. I was stressed out and my sleeping, healthy eating habits, and workout regimen all suffered. At the end of the month I got my testosterone levels tested and found that my total T was 383 ng/dL and my free T was 7.2 pg/mL – close to the average for an 85-100-year-old man.
When you’re under stress (be it from lack of sleep, workplace stress, emotional stress, stress from a bad diet, overtraining etc.), your body releases cortisol. Cortisol blunts the effects of testosterone (47), which makes sense from an evolutionary point of view – if we were stressed as cavemen chances are it was a life or death situation – not running late to a meeting - in this state (i.e. running from a lion) the body wouldn’t care if you couldn’t get it up, there was more to worry about!

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.
Great article with a lot of useful information. I completely agree with your top three picks. I have done a ton of research as well. Currently I am taking Testogen for over two months and it has worked for me. It has double my low T and I am 61 years old. I do feel better and have more energy. Even have morning wood sometimes and haven’t for a long time.

Male hypogonadism becomes more common with increasing age and is currently an under-treated condition. The diagnosis of hypogonadism in the aging male requires a combination of symptoms and low serum testosterone levels. The currently available testosterone preparations can produce consistent physiological testosterone levels and provide for patient preference.


Cross-sectional studies have found a positive association between serum testosterone and some measures of cognitive ability in men (Barrett-Connor, Goodman-Gruen et al 1999; Yaffe et al 2002). Longitudinal studies have found that free testosterone levels correlate positively with future cognitive abilities and reduced rate of cognitive decline (Moffat et al 2002) and that, compared with controls, testosterone levels are reduced in men with Alzheimer’s disease at least 10 years prior to diagnosis (Moffat et al 2004). Studies of the effects of induced androgen deficiency in patients with prostate cancer have shown that profoundly lowering testosterone leads to worsening cognitive functions (Almeida et al 2004; Salminen et al 2004) and increased levels of serum amyloid (Gandy et al 2001; Almeida et al 2004), which is central to the pathogenesis of Alzheimer’s disease (Parihar and Hemnani 2004). Furthermore, testosterone reduces amyloid-induced hippocampal neurotoxity in vitro (Pike 2001) as well as exhibiting other neuroprotective effects (Pouliot et al 1996). The epidemiological and experimental data propose a potential role of testosterone in protecting cognitive function and preventing Alzheimer’s disease.
"A lot of the symptoms are mirrored by other medical problems," Hedges says. "And for a long time, we were not attributing them to low testosterone, but to diabetes, depression, high blood pressure, and coronary artery disease. But awareness and appreciation of low testosterone has risen. We recognize now that low testosterone may be at the root of problems."
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