On the contrary Q: You recommend testosterone replacement therapy for men, but everything I've read and heard says that testosterone increases the risk of prostate cancer. Can you explain why your advice is in direct opposition to this theory? Dr. Wright: For more than 60 years, conventional medicine has preached about the supposed connection between high testosterone levels and an increased risk of prostate cancer. My question has always been: What's the basis for that theory? The answer: There is none. After all, if there were a connection, men between the ages of 18 and 25-the ones who have the highest testosterone levels-would have the highest rate of this cancer. Obviously, that's not the case. But reasoning from Nature and common sense cuts very little ice in mainstream medicine. But when Harvard speaks, it's a different story. Two years ago, a Harvard Medical School urologist wrote: "There is an absence of scientific data supporting the concept that higher testosterone levels are associated with an increased risk of prostate cancer. Specifically, no increased risk of prostate cancer was noted… These results argue against an increased risk of prostate cancer with testosterone replacement therapy." And two years prior to that, prominent Swedish researchers had reached the same conclusion. They studied testosterone levels in 708 men who were diagnosed with prostate cancer and in 2,242 men who did not have prostate cancer. They discovered that the risk of prostate cancer was actually lower in men with higher blood levels of testosterone-the exact opposite of what mainstream medicine has been preaching all these years. So if you're using supplemental testosterone to prevent one of the many conditions it can be used for-cognitive decline, cardiovascular disease, bone loss, maintenance of reasonable sexual function-you can relax a bit about any supposed prostate cancer risk from that testosterone. But let me be very clear: That doesn't mean you should neglect periodic physical exams and the PSA blood test! Even though testosterone itself doesn't cause prostate cancer, something does-even though that cause is still a mystery at this point. But whatever the cause, your best bet is to detect this disease early while it's still treatable--and having regular exams is the only way to do that. Source:
"Testosterone replacement therapy and prostate risks: where's the beef?" Can J Urol. 2006; 13(1):40-3 | 
