Every male needs to take an aggressive approach to protect himself from prostate cancer. If you've grown up in a Western society, then you have spent decades eating beef (especially) and other meats cooked at high temperatures. That delicious black residue on your meat is filled with various cancer causing agents such as HCA's (heterocyclic amines) that head straight for your prostate. (The typical fast food burger, that we literally live and die for, is loaded with the stuff.)Many aspects of the Western lifestyle increase risk for prostate cancer and current lifetime estimates are 16%. 
Many of you have also consumed huge amounts of dairy - another huge risk factor for prostate cancer. Again, to protect yourself from prostate cancer, you have to realize that you have no time to waste: the "seeds of destruction" have already been planted through significant free radical and DNA destruction inside the delicate tissue of your prostate. In addition, many of you are overweight, which puts a significant and potentially deadly estrogen load on your prostate.
NOTE: You should also check out my page How to Lower Your PSA, which shows the latest research on how to lower your PSA, and my page that discusses the research on Does Testosterone Therapy (TRT) Cause Prostate Cancer?.
But the good news is that research has shown us that you can drastically lower your odds of prostate cancer through simple dietary and lifestyle measures. I've listed below some of the most critical foods that you can eat (or avoid in some cases) to very significantly protect yourself from prostate cancer.
Another huge question in the minds of many males is "will HRT (testosterone supplementation) put me at risk for prostate cancer"? Several large, well done studies - see below - have showed this not to be the case. Talk to your doctor, of course, but the evidence looks very positive for testosterone therapy.
Below are several studies that show normal testosterone levels and supplementation are actually healthy for the prostate:
You may have a concern if you have heard or read that sometimes doctors will treat certain prostate cancers by decreasing androgens, i.e. signficantly lowering testosterone. The reason that this is done is that testosterone actually suppresses t-lymphocyte immune response. So some doctors feel that your body can more aggressively attack the prostate cancer with testosterone out of the way. As a side note, this may be why females more frequently develop autoimmune diseases: their immune response in some cases may be too strong due to a lack of testosterone.
Benign Prostate Hypertrophy (BPH)
One other worthy subject with regards to the prostate is protecting yourself against prostate enlargement, which leads to difficulty urinating and a host of other problems.. Current research shows that vegetables, in particular, protect against BPH. One recent study  showed that vegetables rich in lutein, beta-carotene and Vitamin C were particularly protective. (Note: Fruit consumption did NOT correlate with increased protection from BPH. Furthermore, getting these nutrients from supplements did not correlate well either.) But most protective are actually onions and garlic. In one 2007 study onions decreased the risk of BPH by 60% and garlic by 30%.  For more information, please read this link on Protecting Your Prostate from BPH.
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