Both testosterone and 5α-DHT are metabolized mainly in the liver.[1][151] Approximately 50% of testosterone is metabolized via conjugation into testosterone glucuronide and to a lesser extent testosterone sulfate by glucuronosyltransferases and sulfotransferases, respectively.[1] An additional 40% of testosterone is metabolized in equal proportions into the 17-ketosteroids androsterone and etiocholanolone via the combined actions of 5α- and 5β-reductases, 3α-hydroxysteroid dehydrogenase, and 17β-HSD, in that order.[1][151][152] Androsterone and etiocholanolone are then glucuronidated and to a lesser extent sulfated similarly to testosterone.[1][151] The conjugates of testosterone and its hepatic metabolites are released from the liver into circulation and excreted in the urine and bile.[1][151][152] Only a small fraction (2%) of testosterone is excreted unchanged in the urine.[151]
This is an important herb which has been used as therapeutic for centuries. It helps in improving sexual desires and boosts T levels. It is also useful in erectile dysfunction by raising T levels. People having normal T level don’t get affected by taking Tribulus. With the testosterone boosting qualities of Tribulus, this natural supplement works great for building muscle and gaining strength in the gym.

Vitamin D supplementation may potentially boost testosterone levels, but further research is needed to determine if it really has an effect on the testosterone levels of young people and athletes. The truth is likely similar to zinc and magnesium — being in a deficient state causes your testosterone levels to drop below baseline, and supplementing it just takes you right back to baseline (but not any higher).
While it would be nice to buy a testosterone pill from the local supplement store and have your testosterone levels go up, such a magic pill does not exist. As you can see from the above rundown, while a few supplements may be somewhat effective if your T levels are already low, none will significantly raise your testosterone above a baseline level. Thus, the basics of keeping your T levels high remain pretty simple:
Next, while testosterone levels do decline with age, this may simply be because the older that men get, the less they take care of themselves – they stop exercising, start putting on weight, and don’t pay as much attention to their diet. A recent study suggests that age-related T decline is not inevitable, and that if you keep living a healthy lifestyle, you can maintain healthy testosterone levels. So if you’re an older guy, try to do all you can as far as lifestyle changes before you get on the prescription T. I don’t mean doing a little cardio a few times a week, using the machines at the gym, and eating “pretty” healthy. Follow the guidelines above, and see what happens first.
Dr. Anthony's Notes: I like Tribulus. It is a VERY common herb in almost all testosterone boosting products – again though, it may be more of a libido enhancer than anything. From my personal experience, it's effective when stacked with the other libido enhancing supplements in this guide. How To Take Tribulus: Take 200-400mg once per day of a 45-60% saponin extract product.
14. Volek JS, Volk BM, Gómez AL, Kunces LJ, Kupchak BR, Freidenreich DJ, Aristizabal JC, Saenz C, Dunn-Lewis C, Ballard KD, Quann EE, Kawiecki DL, Flanagan SD, Comstock BA, Fragala MS, Earp JE, Fernandez ML, Bruno RS, Ptolemy AS, Kellogg MD, Maresh CM, Kraemer WJ. Whey protein supplementation during resistance training augments lean body mass. J Am Coll Nutr. 2013;32(2):122-35. PMID: 24015719
In fact, high cortisol deals a crushing blow to testosterone in two ways. During, long-lasting stress, high amounts of cortisol release very often and have a direct negative influence on T levels. Thus, cortisol inhibits testosterone synthesis in the testes and hypothalamus. In addition, the production of cortisol is impossible without cholesterol. But testosterone synthesis also demands cholesterol. Since during stress cholesterol is first of all used for making cortisol, T levels simply plummet.
Pellets. Your doctor will place the testosterone pellets under the skin of your upper hip or buttocks. Your doctor will give a shot of local anesthesia to numb your skin, then make a small cut and place the pellets inside the fatty tissues underneath your skin. This medication dissolves slowly and is released over about 3-6 months, depending on the number of pellets. 
Erectile dysfunction is a common finding in the aging male. A prevalence of over 70% was found in men older than 70 in a recent cross-sectional study (Ponholzer et al 2005). Treatment with phosphodiesterase-5 (PDE-5) inhibitors is proven to be effective for the majority of men but some do not respond (Shabsigh and Anastasiadis 2003). The condition is multi-factorial, with contributions from emotional, vascular, neurological and pharmacological factors. The concept of erectile dysfunction as a vascular disease is particularly interesting in view of the evidence presented above, linking testosterone to atherosclerosis and describing its action as a vasodilator.
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.
Sharma, R., Oni, O. A., Gupta, K., Chen, G., Sharma, M., Dawn, B., … & Barua, R. S. (2015, August 6). Normalization of testosterone level is associated with reduced incidence of myocardial infarction. European Heart Journal, 36(40), 2706-2715. Retrieved from