A 12-month study found that supplementing with around 3,000 IU of vitamin D3 per day increased testosterone levels by around 25%. In the elderly, vitamin D and calcium also optimized testosterone levels, which led to a reduced risk of falling. To boost testosterone and reap the other benefits of vitamin D, try to get regular exposure to sunlight or take around 3,000 IU of a vitamin D3 supplement daily.
^ David KG, Dingemanse E, Freud JL (May 1935). "Über krystallinisches mannliches Hormon aus Hoden (Testosteron) wirksamer als aus harn oder aus Cholesterin bereitetes Androsteron" [On crystalline male hormone from testicles (testosterone) effective as from urine or from cholesterol]. Hoppe-Seyler's Z Physiol Chem (in German). 233 (5–6): 281–83. doi:10.1515/bchm2.1935.233.5-6.281.
Testosterone replacement therapy (TRT), expensive testosterone boosters and pills come with more threats and side effects. These threats and side effects are sleep apnea, mild fluid retention or increased risks of having prostate cancer. Besides, these methods cost a lot of money. This makes these options simply not possible for a lot of men. On the other hand, increasing your testosterone level and getting back your youth is possible by making small lifestyle changes. The best therapy is simply a natural testosterone booster. An upgrade of your eating choices can be a simple yet a sure way of getting back your manhood.

Dr. Wassersug, whose background is in evolutionary biology, also noted that lower testosterone in older men may be adaptive, a positive benefit, as our bodies age and become increasingly frail. "The argument can be made," he said, "that it's not beneficial to have the mindset of a 19-year-old when you are 49-years-old, because if you are aggressive enough to get into a conflict with an actual 19-year-old, you are going to get killed."
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.
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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