It's not enough just to increase the testosterone your body produces, because as we age, the testosterone we naturally produce is often bound by SHBG (sex hormone binding globulin) thus becoming unavailable for use in the body. It’s imperative that your testosterone remains unbound or “free” if you want to enjoy all the wonderful benefits testosterone provides.
Finally, related to the point about competitiveness above, studies have shown that testosterone levels not only go up before a fight or competition, they increase after each win, and this gives the winner a much higher probability of winning his next round, and the next round after that, even against evenly matched competitors. This is called the “winner-effect,” and John Coates, author of The Hour Between Dog and Wolf: Risk Taking, Gut Feelings and the Biology of Boom and Bust, explains why it works:

Vitamin D and zinc are both essential to testosterone production. A year-long study looked at the vitamin D and testosterone levels of 2299 men. It found that men with vitamin D levels above 30 nmol/L had more testosterone and lower levels of sex hormone-binding globulin (SHBG). SHBG binds to hormones so your cells can’t use them, and if you have too much of it, your testosterone levels drop [8]. Men with vitamin D deficiency had lower testosterone and higher SHBG levels.


Zinc deficiency also negatively affects testosterone levels, according a 2014 article in the Journal of Plant Biochemistry and Physiology. The authors of this review note that zinc supplementation can increase circulating testosterone in some populations. In fact, daily supplementation with typical doses may double testosterone within a few months.
There are pills in the United States for testosterone supplementation, but their use is strongly discouraged because they cause significant liver toxicity. A safe oral formulation called testosterone undecanoate is available in Canada and in Europe, but not in the United States. What’s quite exciting is that an injectable version of testosterone undecanoate (Nebido) was submitted to the FDA for approval in August 2007. (It’s already approved in many other countries.) It lasts for 12 weeks, so a patient could come in and get a shot about four times a year. [Editor’s note: In December 2009, the brand name of the drug in the United States was changed to Aveed. As of January 2011, it was still awaiting FDA approval.]

I know the experiment didn’t simply bring me back to my pre-August levels because of the fact that when I learned that the original test I took can sometimes overestimate your T levels, I took a more accurate test around four months after the start of the experiment (I’ve continued the lifestyle changes made during the experiment) and my total T had gone up again to 826.9 ng/dL.
One more thing that I have experienced from getting injected T is that my testicles have shrunk and they have shrunk quite a good amount. I would say that my testicles are about half the size they were just 4 months ago. This is a result that many men get when they get T injections. I have a buddy who also gets injections and his testicles have shrunk a good amount as well. It’s not a bid deal overall as I am 51yrs old and things like that are not bother. However, I do miss feeling/having larger testicles when I catch a glimpse in the mirror or “adjust” my private parts and I can feel less there. 🙂
Cardiovascular disease, and its underlying pathological process atherosclerosis, is an important cause of morbidity and mortality in the developed and developing world. Coronary heart disease in particular is the commonest cause of death worldwide (AHA 2002; MacKay and Mensah 2004). As well as increasing with age, this disease is more common in the male versus female population internationally, which has led to interest in the potential role of sex hormones in modulating risk of development of atherosclerosis. Concerns about the potential adverse effects of testosterone treatment on cardiovascular disease have previously contributed to caution in prescribing testosterone to those who have, or who are at risk of, cardiovascular disease. Contrary to fears of the potential adverse effects of testosterone on cardiovascular disease, there are over forty epidemiological studies which have examined the relationship of testosterone levels to the presence or development of coronary heart disease, and none have shown a positive correlation. Many of these studies have found the presence of coronary heart disease to be associated with low testosterone levels (Reviews: Jones, Jones et al 2003; Jones et al 2005).
Hypogonadism is a disease in which the body is unable to produce normal amounts of testosterone due to a problem with the testicles or with the pituitary gland that controls the testicles. Testosterone replacement therapy can improve the signs and symptoms of low testosterone in these men. Doctors may prescribe testosterone as injections, pellets, patches or gels.
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