Enough with stories about who's fat

Editor's note: Howard Kurtz is the host of CNN's "Reliable Sources" and is Newsweek's Washington bureau chief. He is also a contributor to the website Daily Download.

(CNN) -- Can the media get over their collective obsession with weight?

Fat chance.

For some strange reason, here we are again, talking about Michelle Obama's derriere. And, for good measure, Chris Christie's girth.

Watch: Why is Washington Post highlighting Michelle Obama's rear?

It's easy, it's fun, it's good for clicks and ratings. It's also kinda cheap.

Howard Kurtz

The Washington Post used a pretty flimsy peg -- Alabama high school football coach Bob Grisham caught on tape -- to run a Style section piece on the weighty issue. "Fat butt Michelle Obama," the coach is heard saying, declaring her overweight. Grisham was suspended by the school (he says he misspoke).

But this is national news? Really?

Talk Back: Should Christie be shamed into losing weight?

Of course, the paper dressed it up with highfalutin' sociology. "The focus on this first lady's posterior has historical antecedents," the article says, launching into questions about how black women have long faced scrutiny about their bodies.

Well, maybe. And yes, Rush Limbaugh and Republican Rep. James Sensenbrenner have sounded off about Obama's bottom. And yes, the fact that she has mounted an anti-obesity campaign does sort of put her in the crossfire.

Watch: Chris Christie's doughnut diplomacy with Letterman

But as the Post acknowledges, Michelle Obama is a 5-foot-11-inch woman with toned arms who is widely viewed as being in good shape. She's not a triathlete; she's a working mother of two. So when the story asks, "What is it with Michelle Obama's critics and the fixation with her derriere?" I would turn that question around. What is the media fixation with publicizing it every time some bozo sounds off about her backside?

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Does being overweight determine health?

This is an uncomfortable reminder that the media business celebrates models bordering on anorexic, making perfectly proportioned young girls and women feel heavy because they don't have superthin (and often airbrushed) celebrity bodies. This may help promote the fashion industry, which considers normal women plus-size, but it bears little relation to real life.

Christie is a different case. Having endured endless jokes about his oversized frame, the New Jersey governor shrewdly decided the best path was to poke fun at himself.

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So he appeared on David Letterman's couch this week, one of his chief tormenters, and promptly shoved a doughnut into his mouth. He allowed that he didn't mind fat jokes if they're funny. It was self-deprecating humor that showed Christie to be a real human being.

But the truth is that the teasing does bother Christie. And there is a serious question here beneath the laughter. Christie is grossly overweight, and his health would be a legitimate issue if he runs for president in 2016. Which, as you may have noticed, is four years from now.

Doughnuts aside, Christie treated the matter more seriously at a news conference, saying that he's "remarkably healthy" but that "my doctor continues to warn me that my luck is going to run out relatively soon."

The governor showed he had lost none of his feistiness after Connie Mariano, a former White House physician, said on CNN: "I worry that he may have a heart attack, he may have a stroke. ... I worry about this man dying in office."

Christie upbraided her Wednesday for diagnosing him without an examination: "She must be a genius. She should probably be the surgeon general of the United States." He said she was just another hack seeking "her five minutes on TV."

Well, you started it with your doughnut diplomacy, Governor.

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If Christie becomes a White House contender, everything is fair game. He can hardly complain about other folks after his "Late Show" shtick. But I can't help but think it is easier for pundits to pontificate about Christie's weight than to examine his record in Trenton.

Everyone who has worried about those extra pounds can relate to the story, but the coverage is out of hand.

If I never read another word about Michelle Obama's behind, I may go celebrate with a Krispy Kreme.

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The opinions in this commentary are solely those of Howard Kurtz.