In a recent review of the blaxploitation spoof “Black Dynamite” (a movie that will apparently never open here), critic Roger Ebert wrote the following:

“I am happy to say it brings back an element sadly missing in recent movies, gratuitous nudity. Sexy women would ‘happen’ to be topless in the 1970s movies for no better reason than that everyone agreed, including themselves, that their breasts were a genuine pleasure to regard – the most beautiful naturally occurring shapes in nature, I believe. Now we see breasts only in serious films, for expressing reasons. There’s been such a comeback for the strategically positioned bed sheet, you’d think we were back in the 1950s.”

I lack the cultural influence to be that unapologetic of my heterosexuality in print, but Ebert brings up a good point.

What did happen to gratuitous nudity?

In the ’70s and ’80s, almost all R-rated films had some of it – “R” being the most commercially viable rating at the time.

Gratuitous nudity (usually of the female variety) was a favorite of feminists, moralists and underage boys.

The first two groups liked to foment against it and the last group was sort of an underground support movement; which is to say, underage boys bought tickets for movies that didn’t have gratuitous nudity and sneaked into films that did have it. Now there is very little of it to be had at the multiplex.

I am not sure who coined the phrase “gratuitous nudity,” but it’s not very apt. It is meant to signify “nudity that is not essential to the plot.”

But 30 years ago, when a studio would run tests and discover that a film in production had undetectable levels of plot, nudity became the opposite of gratuitous. It was indispensable – the cheapest special effect there was.

Gratuitous also seems to imply unobtrusive to me, as long as I steer clear of dictionaries or thesauri.

But most of this nudity, at least the stuff that happened in teen sex comedies and cop movies of the ’80s, was glaringly and blaringly absurd. It made no real-world sense: desk clerks at resorts who just happened to be naked, coeds strolling the halls of dorms all day wearing nothing but incompetently tied towels.

Remember how all important meetings in ’80s cop movies always happened in strip clubs?

While I believe that a dissipated movie cop might gravitate to a strip club for the booze, I do not believe he would be at all interested in the cover charge, the noise, the larcenous drink prices or even the titillation.

These sorts of scenes weren’t exactly respectful of women (well, duh!) and the fact that they are less prevalent in mainstream movies these days might have something to do with inroads made by the women’s movement, according to Robert Bulman, associate professor of sociology at Saint Mary’s College of California.

“The women’s movement of the 1970s was very successful in changing (for the better) the way in which American culture regards women’s bodies,” Bulman writes in an e-mail. “Rather than simply props in a movie that gratuitously attract heterosexual male attention, women in movies began to develop more substantive character.”

It is much easier these days for a new actress like Megan Fox, Scarlett Johansson or Jessica Alba to insist on a “no nudity” clause in her contract and, all durable masculine lasciviousness aside, this is vastly preferable to the days when nudity was just the price that actresses paid for wanting to be successful.

Obviously, as Bulman points out, “nudity is not the only way to objectify (women).”

The fact that the PG-13 rating has become more lucrative than the R rating is certainly another reason why there is less nudity in mainstream films. But less nudity hasn’t necessarily meant less sexism and stupidity.

Just look at the portrait of college life painted by “Transformers 2: Revenge of the Fallen.”

It’s indistinguishable from that of an ’80s teen sex comedy, except it’s even less wholesome: All the women are hard-eyed, randy lingerie models and all the guys are opportunistic con artists.

But because no one gets naked, it is allegedly “family-friendly.”

That’s the problem I have with the PG-13 rating.

Families attend these movies thinking they’re safe, but they are often the result of studios trying to be stealthier about slipping in as much of the old salaciousness and ultraviolence as before.

And while I have no proof of this, it seems that violent content that once earned an R rating has migrated down into the PG-13 rating and onto cable, basic cable and even commercial television.

“What is interesting is that while what is permissible regarding nudity and sexual activity have become more strictly and narrowly defined in Hollywood films,” writes Central Michigan University film professor Ken Jurkiewicz in an e-mail, “most of the limits regarding brutal and graphic violence have been erased or expanded exponentially …”

Of course, it is silly to get nostalgic about gratuitous nudity, and I won’t get caught doing it.

As Jurkiewicz puts it, “does any moviegoer with even a trace of self-respect really wish to return to the glorious days of ‘Showgirls’?”

But it was a more innocent time (I can’t believe I just typed that), a time before the

Internet brought nudity and everything a person can (but not should) do while naked into people’s living rooms (which is to say, home offices).

I suspect that what Ebert misses isn’t so much gratuitous nudity as confident, matter-of-fact nudity, like the nudity on display in the remake of “The Thomas Crown Affair.”

Here you have a film that was not made for teens in which adult characters do adult things for adult moviegoers, and some of these things involve nudity (although they don’t usually involve nude moviegoers).

Nudity that isn’t used to perpetuate an immature, piggish and sexually stunted vision of the universe can be quite refreshing.

Head for the Web

This week’s Web exclusive is my rundown of all the TV commercials that I really hate right now, including those for a tween version of “Dora the Explorer.”

Trust me: It’s funnier than it sounds. You can find it on The Journal Gazette’s arts and entertainment blog, Get a Load of This, at www.journalgazette.net/getaload.