I know this is really controversial and there’s a lot of pseudoscience involved. however, I have noticed some subtle benefits from long term Semen retention. The main one is more stable positive mood and slightly increased motivation.
You won't get reassurance from the scientific community, or the average person who believes wholeheartedly in science, because science treats the subject from a purely mechanistic viewpoint. What matters is what it does
for you, and you've done the experiment yourself.. which ironically is science.
Absolutely it has benefits. I've done it myself - twice I've done 6+ month streaks. At around the 6 month mark I began to notice quite a shift in my mental state, my mind became very calm indeed, and it made me aware of just how much the background turbulence of our minds obscures the light for lack of a better term. It's like our minds are like the surface of a pond, and ordinarily the surface is a bit choppy, but you can still just about make out the reflections on the surface, but when the water becomes completely still you can see the reflections with tremendous clarity
and you can see the light source itself. You don't know what you're 'missing' if you've never experienced it - the ordinary turbulent state does not hinder ordinary functioning, obviously, but one can immediately see the implications of the state of clarity if one is practicing an inner discipline (which is why celibacy figures in just about all spiritual paths).
But, celibacy is a science. You only need look to the Catholic Church to see the negative results of what it can do when it is not treated with the respect it demands. The sexual force is one of our most potent energies, it drives so much of our psychology.
The trouble with the RC Church, and the 'no fap' movement, is they try to build a dam first without considering how that potential is to be harnessed (transmuted). They do not have the blueprints for the outlet and the power turbines to make use of all that stored up potential. The energy has to go somewhere, you have to have an outlet, or the water will destroy the dam eventually. On a physical level the body is not meant to function this way, which is where science is correct,
especially if you are teasing yourself with sexual imagery and causing the prostate to activate without release.. which puts tremendous pressure on it and can be dangerous as you get older and the prostate becomes less flexible (prostatitis). Also, if your diet and rest of your health is poor, this can lead to stagnation and accumulation of toxins in the prostate fluid, which again can cause illness and possibly cancer.
You have to not put the cart before the horse. You need the outlet (transmutation) plans
first. This doesn't need to even be a spiritual discipline, but any mental pursuit that requires concentration and demands mental energy will drive the system that naturally draws the energy upwards. The desire for sex will be naturally diminished, and this is quite a common experience.. when people are so focused on work etc that the desire for sex seems to dissipate.
What the 'no fap' people get wrong is they make a religion out of it, when it should be a science. For example, nowhere does anyone talk about tapering off. All breastfeeding women know that you can't just stop milk production abruptly, you have to wind the process down or you'll get caked ducts, and the same goes for men.. because it's about glands, and glands take time to adjust to frequency of use.
Personally, I find I'm happiest at about the 1-2 week mark between emissions. It's enough to keep the body happy, but also long enough between emissions to keep the mind less turbulent which means my mental pursuits become more efficient. I'm thinking about doing another long period of celibacy though because I want to get back into serious lucid dreaming and astral projection again, and that requires a bit of extra mental energy.