It's not much of a secret what guys do when they look at Porn. We do need to talk about masturbation in order that the conversation around Porn be complete. For me it is sometimes like smoking to heroin addicts. It seems harmless by comparison, but is addictive and brings death just the same. I realize my stance on this issue may seem a little more rigid than some, but I hope I can give some different perspective to an issue I think we are very uncomfortable to talk about.
The most damaging aspect of masturbation is that it reinforces a pathology of control. Usually masturbation centers around a very specific ritual. Over time the brain will actually increase serotonin levels in response to this ritual. The brain can actually become addicted to this increased serotonin in the brain. This level of addiction has been ranked as being on par or greater than heroin. Of course this addiction reinforces the desire to participate in the ritual. So the individual trapped in this enters a marriage relationship and all the sudden sex is more spontaneous. There are distractions and lots of things that can not be controlled. The serotonin in the brain is actually lower, because the specifics of the ritual are not being followed. Masturbation has the potential to destroy sex in a marriage.
Masturbation is also an entirely selfish act. The only objective is to satisify one's self. Healthy sex involves focusing on giving your wife pleasure, not yourself. Masturbation perverts healthy sexual desire and makes it all about gratifying one's self.