This is a must read article and I encourage you to read the whole thing.

Young people who have been exposed to pornography are more likely to have multiple lifetime sexual partners, more likely to have had more than one sexual partner in the last three months, more likely to have used alcohol or other substances at their last sexual encounter, and—no surprise here—more likely to have scored higher on a “sexual permissiveness” test. They are also more likely to have tried risky forms of sex. They are also more likely to engage in forced sex and more likely to be sexual offenders.

As for the all-purpose cop-out that “all this shows is correlation,” it can be refuted as Dr. Johnson famously refuted the immaterialism of Bishop Berkeley—by kicking a stone. No one reasonable would doubt that there is a connection between watching sex acts and trying out what one sees—especially for adolescents, who rather famously and instantly ape the other influences on their lives, from fashion to drug use and more, as has also been copiously studied.

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But even this impressive array of data cannot answer a question almost as ubiquitous as pornography itself: So what? Why should people who are not part of that consumption even care about it? The varieties of the libertarian shrug extend even to those averse to it. Pornography indeed may be morally wrong, many of those people would also say (and of course major religions would agree); but, apart from the possible damage to the user’s soul, if you believe in such a thing, what really is the social harm of smut?

This lackadaisical attitude—this entrenched refusal to look seriously at what the computer screen has really wrought—is widespread. Religious people, among other people simply disgusted by the subject, understandably wish to speak in public of almost anything else. Closet users, and they are apparently legion, will probably already have stopped reading these words—or any others potentially critical of pornography—for reasons of their own; such complicity is probably the deepest font of omertà on the subject. And chronic users above all have their own fierce reasons for promoting the anything-goes-as-long-as-it’s-private patter—an interesting phenomenon about which more will be said further on.

And yet this hands-off approach to the matter of sexual obesity—this unwitting collusion of disparate interested parties masquerading as a social consensus—remains wrong from alpha to omega, as a new document signed by fifty experts from various fields and distilling just some of the recent empirical evidence, goes to show. Full disclosure: “The Social Costs of Pornography: A Statement of Findings and Recommendations,” just published by the Witherspoon Institute of New Jersey, was codrafted by Mary Ann Layden and me. Unlike other pieces of writing, however, this compendium summons no authorial joy and is not the work of one or two but rather scores of people. Most of them academics and medical professionals, they represent a true rainbow coalition of the spectrum: left and right, feminism and conservatism, secularism, Judaism, Christianity, and Islam. It’s a collective attempt to render for the public good just some of the accumulating academic and therapeutic and other evidence of the harm and devastation now traceable to pornography abuse.

Bursting through the academically neutral language, the studies, the survey data, and the econometrics were the skin and bones of the very human stories that went into it all: the marriages lost or in tatters; the sexual problems among the addicted; the constant slide, on account of higher tolerance, into ever edgier circles of this hell; the children and teenagers lured into participating in various ways in this awful world in the effort to please romantic partners or exploitive adults. This report, in sum, like the conference that preceded it, answers definitively the libertarian question of “So what about pornography?” with a solid list of “Here’s what”—eight documented findings about the manifold risks of warping the sexual template with pornographic imagery.

See also this related link.