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]
Many clinical studies have looked at the effect of testosterone treatment on body composition in hypogonadal men or men with borderline low testosterone levels. Some of these studies specifically examine these changes in older men (Tenover 1992; Morley et al 1993; Urban et al 1995; Sih et al 1997; Snyder et al 1999; Kenny et al 2001; Ferrando et al 2002; Steidle et al 2003; Page et al 2005). The data from studies, on patients from all age groups, are consistent in showing an increase in fat free mass and decrease in fat mass or visceral adiposity with testosterone treatment. A recent meta-analysis of 16 randomized controlled trials of testosterone treatment effects on body composition confirms this pattern (Isidori et al 2005). There have been less consistent results with regard to the effects of testosterone treatment of muscle strength. Some studies have shown an increase in muscle strength (Ferrando et al 2002; Page et al 2005) with testosterone whilst others have not (Snyder et al 1999). Within the same trial some muscle group strengths may improve whilst others do not (Ly et al 2001). It is likely that the differences are partly due to the methodological variations in assessing strength, but it also possible that testosterone has different effects on the various muscle groups. The meta-analysis found trends toward significant improvements in dominant knee and hand grip strength only (Isidori et al 2005).
Both Beast Sports’ Super Test and iSatori’s ISA-Test contain a proprietary blend, which means they don’t disclose the amount of each and every ingredient in the mix. This is only a problem if there is an ingredient tucked into a proprietary blend for which we need to know an amount, like magnesium and zinc. While none of the ingredients in Beast Sports’s proprietary blend raised any red flags, iSatori’s blend contains melatonin, a hormone that helps regulate sleep. Melatonin is an ingredient that has a hard upper limit — Healthline suggests at most 10mg for an adult — and even lower doses can interact poorly with many medications. Since we can’t confirm whether the amount of melatonin in iSatori’s proprietary blend is under 10mg, we cut iSatori.
We kept it simple, and followed the premise of testosterone boosters: testosterone affects muscle gain, weight loss, and libido, so by increasing the amount of testosterone in the body, we can improve on each of those goals. This meant that we looked for ingredients proven to increase testosterone levels, not ingredients that might increase libido or help build muscle mass independently of testosterone (like having a healthy diet and feeling good about yourself). In addition, we dove deep into the specific ingredient lists of our finalists and cross-checked them against WebMD and the National Institutes of Health (NIH) database to make sure that they did not contain ingredients known to be harmful.
Every vitamin, mineral, and ingredient that affects the human body can be taken in enough quantities that they are harmful, or toxic, even the ones that — at lower levels — are beneficial or necessary. Unfortunately, testosterone boosters contain a lot of ingredients that are not well understood. This means in addition to not being able to confirm whether certain ingredients increase testosterone, the scientific and medical communities also don’t know at what levels many ingredients become toxic. On the up side, you might need to eat several pounds of a particular leafy plant before it becomes harmful. On the down side, it could be significantly less that pushes you over your body’s limit. We simply don’t know how little or how much the human body can tolerate. We recommend keeping your doctor in the loop when you add any supplement with unproven ingredients into your diet — they’ll be able to help you find and track any undesired side-effects that these ingredients might cause.
As a matter of fact, not only oysters are good for testosterone production. Any shellfish from the class bivalve mollusk is. This is because when you eat a shellfish, you are sure that the whole animal is eaten. That includes the muscle meat, digestive tissue and organ mass. As a result, no other source of protein packs so much of variety in such a compact manner. Make shellfish a staple part of your daily diet to see yourself brimming with testosterone.
It also has vitamin B6. One study called out folate and vitamins B6 and B12 as important nutrients for athletes to achieve optimal health and performance. Vitamin B6 is commonly found in food, like fortified cereals, and as with magnesium, it’s possible to have too much vitamin B6. The NIH recommends an upper daily limit for adults of 100mg per day. Beast Sports comes well under this limit at 10mg per day, but still well above the minimum recommended dose of 1.7mg needed to see benefits.
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Richard J. Wassersug, PhD, an adjunct professor of urology at the University of British Columbia, described his personal experience with androgen deprivation therapy (ADT). "If you are on ADT," he said, "and you see those Low T ads, what are you supposed to make of it? This produces a cognitive dissonance." He called the ads "hurtful" for suggesting that low testosterone makes a man less of a man.
For men with low blood testosterone levels, the benefits of hormone replacement therapy usually outweigh potential risks. However, for most other men it's a shared decision with your doctor. It offers men who feel lousy a chance to feel better, but that quick fix could distract attention from unknown long-term hazards. "I can't tell you for certain that this raises your personal risk of heart problems and prostate cancer, or that it doesn't," Dr. Pallais says.

6)  Take Cold Showers:  Cold showers have been known to stimulate and boost testosterone production and improve metabolism, detoxification and brain function.  Start your shower with warm/hot water and turn it to cold for the last 30-60 seconds while pumping your muscles and creating a big shiver as your muscles contract.  That will help to boost internal heat and boost testosterone production.  This article will help you.

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.
A related issue is the potential use of testosterone as a coronary vasodilator and anti-anginal agent. Testosterone has been shown to act as a vasodilator of coronary arteries at physiological concentrations during angiography (Webb, McNeill et al 1999). Furthermore men given a testosterone injection prior to exercise testing showed improved performance, as assessed by ST changes compared to placebo (Rosano et al 1999; Webb, Adamson et al 1999). Administration of one to three months of testosterone treatment has also been shown to improve symptoms of angina and exercise test performance (Wu and Weng 1993; English et al 2000; Malkin, Pugh, Morris et al 2004). Longer term studies are underway. It is thought that testosterone improves angina due its vasodilatory action, which occurs independently of the androgen receptor, via blockade of L-type calcium channels at the cell membrane of the vascular smooth muscle in an action similar to the dihydropyridine calcium-channel blockers such as nifedipine (Hall et al 2006).
The reasons for considering such therapy become evident from the many associations, indicated above, that reduced testosterone has with a variety of both physiological functions (bone metabolism, muscle mass, cognitive function, libido, erectile function) and pathophysiological states (metabolic syndrome, diabetes mellitus, obesity, insulin resistance, autoimmune disease). Although a definitive long-term, large scale placebo-controlled double-blind study of testosterone therapy in the aging male has not yet been carried out, multiple shorter-term trials have suggested improvement by testosterone with a resultant enhancement of muscle mass, bone density, libido, erectile function, mood, motivation and general sense of well-being.
Now that we know chronic insulin spikes lead to lower Testosterone production, I hope I haven’t sent you running into the low carb camp! There are a few studies out there showing that long term low carb or ketogenic dieting leads to higher cortisol levels (especially with subjects who are training), and decreased testosterone levels (28 & 29). I have used low carb diets in the past with successful results (winning a national bodybuilding title), however the key is to use cyclical carb re-feeds. If you’re going to go on a low carb diet for whatever reason, be sure to work in a large carb reefed once a week.
Because of the mass production, conventional pigs are fed with GMO soy and corn, and they’re living in such horrid conditions that they’re pumped full of antibiotics to ensure that the pigs won’t get any inflammatory diseases, and then they’re fed & injected with ridiculous amounts of estrogen and growth hormone to make the pigs fatter and bigger in record times.
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.
Ashwagandha is shown to be effective at reducing cortisol which in turn helps with testosterone production. There are also numerous studies showing the effects on improving testosterone in infertile men (ref 80).  If you are using the Aggressive Strength product you don't need to supplement with ashwagandha as it's included in the test booster formula. Likewise if you're using Tian Chi (my daily herb drink).

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, 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...
Dr. Anthony’s Notes: I use Maca often in cycles throughout the year. I typically buy the raw Maca powder, which has a VERY “dirt-like” earthy taste. Beware if you are a bit squeamish on tastes! How To Take Maca: 1500-3000mg of Maca powder is a typical dosage take daily alongside food. From personal experience, I've found that it’s best to buy the Maca powder as a standalone supplement and throw it into a blended protein shake to mask the taste.
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).
Like other supplements and medication, testosterone therapy comes with risks and possible side effects. This is particularly true if you try to take it for normal aging rather than for treatment of a condition. Also, the Cleveland Clinic points out that the effects that these supplements may have on your heart and prostate can lead to a number of potential issues. Complications include:
Ten healthy men aged around 24 years old spent 1 week sleeping for 8 hours per night at home, they then spent the next 11 nights in a lab. They slept for 10 hours per night for 3 nights, followed by 8 nights of restricted sleep, when they slept for only 5 hours. Doctors checked their blood every 15 to 30 minutes during the last night that they slept 10 hours, as well as on the sleep-restricted session.
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]
However, if you have normal testosterone levels and are looking for a boost, for strength gaining purposes, then D-Aspartic acid use may prove less fruitful. A study published in Nutrition Research showed that when the booster was given to men who resistance trained four times a week, their body composition and muscle strength was no different to men who took part in resistance training without the aid of D-Aspartic acid.

If a man's testosterone looks below the normal range, there is a good chance he could end up on hormone supplements—often indefinitely. "There is a bit of a testosterone trap," Dr. Pallais says. "Men get started on testosterone replacement and they feel better, but then it's hard to come off of it. On treatment, the body stops making testosterone. Men can often feel a big difference when they stop therapy because their body's testosterone production has not yet recovered."