- Western diet
- Industrialised environment
- Increased androgen receptors
- Oestrogen/testosterone imbalance
Any normal man will develop BPH if he lives long enough. Time and male hormones (dihydrotestosterone and testosterone) are the only proven risk factors for developing BPH.
Prostate cells are much more sensitive to dihydrotestosterone than testosterone itself. An enzyme specific to the prostate, 5-alpha reductase, converts testosterone to dihydrotestosterone. Men who are castrated in their youth, or who lack 5-alpha reductase, do not develop BPH.
Recent studies indicate a probable genetic link for BPH. A male with a first degree relative who has had surgery for BPH has a four times' increased lifetime risk of needing prostate surgery himself. This genetic link is especially strong for men under 60 years of age with large prostates.
Some studies indicate that male hormone receptors (androgen receptors) may be increased in BPH cells. The role of environmental factors such as diet, obesity and an industrialised environment is not entirely clear.
Oriental men (especially the Japanese) have a low incidence of BPH. The oriental diet, which is high in phyto oestrogens, may have a protective effect.
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