There absolutely is, I think it's much more common than men think or would like to admit. Porn distorts the reality of sex, for some people its more subtle but I see a lot of guys who seem to have lost any grip it, they've essentially gone feral.
I used to follow some porn aggregator guy and watched him spiral over the course of maybe ten years or something. It started innocent enough, just catering to a specific not so popular niche, posting once a week or ever few weeks. Then it was daily, then multiple times a day, then all day every day. The content drifted further from the core, becoming more extreme and frankly depraved as he posted more often. I scuttled the ship for that reason, but would check in every now and again. Last I saw he had given up on the internet portion of it entirely. He said he had destroyed friendships and family bonds over it, and it sounded like he was joining some sort of sex cult, bad stuff.
I know this is just once case, but read around the site a bit and you'll see the same symptoms almost everywhere. A lot of people here would be well served to think of Icarus every now and again. I've been tapering off porn myself for some time now and what I used to watch years ago disgusts me now, nature is healing.
TL;DR, moderation is key.
