regular emissions helps prevent prostate cancer ... releases stress, and makes you happy ....
so it's either the hand or the hole ....
however
1. masturbation causes carpal tunnel syndrome, either in one hand, or for a few (lucky ones?), both hands ...
2. lack of lubricants may cause skin abrasions and makes it itch
3. the old uncle's tale that too much masturbation and you won't be able to have sex normally might just be true
4. straight sex is good exercise, you burn a lot more calories this way, and is way more fun
5. masturbation and porn is like bread and butter, you invariably find them together, and porn is not healthy
6. may cause sticky mess on the keyboard, bed, carpet, whatever

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