Great question. I’ve heard a few different statistics about it and it has made me curious as well. So in regular Emma form I go out and research it until I am blue in the face. The short story is- there are lots of proven risk factors but lack of ejaculation doesn’t seem to be one of them.
I’ve seen some speculative links between prostate cancer and orgasm with surveys that try and link ejaculation frequency with prostate cancer. One of them even states that a man should ejaculate 4.7 times per week to have a 30% reduction in prostate cancer. Those surveys don’t take other factors into account such as age, health, weight etc.
They do say that ejaculating frequently clear carcinogenic substances from the testicles. Assuming that is the case, frequent teasing should be more than sufficient to keep things moving. A man who is denied and teased is almost always leaking, which proves that that sperm and hormone production is still in high gear.
Additionally, Semen is a fluid that is made from secretions from the seminal vesicles and secretions from the prostate. If the prostate is full, the man will stimulate his prostate when he defecates. This will release seminal fluid. There are other, more exciting ways of milking the prostate as well.
The short story is – the testicles will keep things flowing with enough stimulation and teasing. The prostate will milk itself during bowel movements as needed by the body. There may be some value in keeping high hormone levels and high levels of arousal, which I highly recommend as well. Don’t lock him and leave him, there are many reasons why that would be a recipe for disaster. Make sure that you check reputable medical information and if you find any studies that you think are reputable, feel free to post them here. Always defer to your doctor’s recommendation yada yada.