What health risks does masturbation have, precisely? You want to speak of health reasons, which are related to Biology specifically, go on then. Please inform me of the exact health risks normal masturbation has to people.
Irritation? Only if you're too rough and do it too often. No one recommends that (unless you like pain.)
And that would preclude you from even scratching yourself when itchy. Doesn't seem like a very good reason to stop altogether to me.
Then of course one extreme is not always the best solution to another extreme. I mean sexual frustration is a thing and is considered quite unhealthy.
Of course, over indulgence could lead to harm in many ways. But you can say that of eating freaking fruits even!! So should we abstain from mandarins, because if you eat enough of those, you can get diabetes? Should one abstain from eating meat, because if one eats nothing but meat you could end up with Scurvy? Should one never have a mobile on them (even for work purposes) because over use has been shown to cause cancer? Should one never run, because if you run too much you risk your body shutting down or even heart attacks?
If we lived our lives based on the absolute worst scenario (in this case over indulgence) we would have to sit in a quiet room all day doing nothing. Which isn't that beneficial and potentially harmful in and of itself even.
Of course if one has an addictive personality they should be careful of literally everything they do (you can get addicted to cereal even.)
But I think the rest of us are safe to partake in anything we want, so long as it doesn't become a problem in our lives.
Oh and as for health concerns masturbation in both male and females has consistently been shown to reduce risk of developing some
cancers.
Happy news! Masturbation actually has health benefits