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Aromatase inhibitors can boost testosterone on their own, but they can also complement other testosterone boosters. If you take a supplement that increases testosterone without inhibiting the aromatase enzyme (through hypothalamic stimulation, for instance), you may find yourself with more estradiol than you need, a situation that taking an aromatase inhibitor may remedy.
A lifelong habit of learning and engaging in mentally challenging activities seems to keep the brain in shape. Intellectual enrichment and learning stimulate the brain to make more connections, increasing the density of nerve-to-nerve connections. That means the "educated brain" may possess a deeper well of connections and be able to withstand more damage to the brain from a small stroke without causing loss of memory or thinking skills.
The finding of hypogonadism in diabetic men is not just a scientific curiosity, it may have practical management implications. Kapoor and colleagues (2006) undertook a placebo-controlled double blind study to determine the effect of testosterone therapy on insulin resistance and glycemic control in hypogonadal men with type 2 diabetes. They found that men treated with testosterone had reductions in glycated hemoglobin insulin resistance, fasting blood sugar, waist circumference, waist/hip ratio and total cholesterol.

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).
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.
The basis for my thinking that T levels could be boosted by cold baths came from a post I wrote a few years ago on the benefits of cold showers. One benefit I found in my research was that they could increase testosterone levels. I mentioned a 1993 study done by the Thrombosis Research Institute in England that found increased T levels after taking a cold shower. Here’s the thing. I can’t find a link to the original source and I can’t find any other studies that support this claim! So without supporting research, I’m unsure of the effects of cold showers on testosterone.
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. 
Testosterone is a steroid from the androstane class containing a keto and hydroxyl groups at the three and seventeen positions respectively. It is biosynthesized in several steps from cholesterol and is converted in the liver to inactive metabolites.[5] It exerts its action through binding to and activation of the androgen receptor.[5] In humans and most other vertebrates, testosterone is secreted primarily by the testicles of males and, to a lesser extent, the ovaries of females. On average, in adult males, levels of testosterone are about 7 to 8 times as great as in adult females.[6] As the metabolism of testosterone in males is more pronounced, the daily production is about 20 times greater in men.[7][8] Females are also more sensitive to the hormone.[9]
Some of these signs and symptoms can be caused by various underlying factors, including medication side effects, obstructive sleep apnea, thyroid problems, diabetes and depression. It's also possible that these conditions may be the cause of low testosterone levels, and treatment of these problems may cause testosterone levels to rise. A blood test is the only way to diagnose a low testosterone level.