In "Just Friends," Ryan Reynolds plays Chris, a guy whose high school love for his friend, Jamie (Amy Smart), goes unrequited ostensibly because he's obese. When he returns to town years later for a second chance, he's slim, successful and sexy. We're willing to wager that in the end, she loved him for who he was underneath all along — but that's just a guess.

Still, while a hefty half of Americans are now overweight, it's another element of our society that's not realistically portrayed in films. Obesity is usually played for laughs or tears; either it's the chubby, comic-relief co-worker/ best friend or the dangerously heavy victim. You're unlikely to see an overweight actor above the title unless it's part of the plot. And even then, the actor might not fit the part.

Dom DeLuise had a healthy career in the '70s and '80s acting in Mel Brooks films, including "Blazing Saddles" and "Silent Movie," and as Burt Reynolds' sidekick in "The Cannonball Run" and "The End." But his only starring role was in 1980's "Fatso," playing an overweight guy who spends a lot of time crying over his food obsession. The Anne Bancroft-directed comedy received a critical and commercial drubbing. These days, DeLuise's acting is mostly relegated to voice work for cartoons, as he seems more interested in selling double chocolate chip coffee cake and posting recipes on his Web site.

Maybe the most poignant screen portrayal of the isolation and ostracism suffered by the obese is 1993's "What's Eating Gilbert Grape?" In the film, Johnny Depp plays a troubled teen who cares for his mentally retarded brother (Leonardo DiCaprio) and a morbidly obese mother (Darlene Cates). While he is loath to admit it, Gilbert is ashamed of his mother, and she can tell. First-time actress Cates' performance was the definition of Method acting: she weighed 500 pounds in real life. Most actors who play huge do so in what's referred to as a "fat suit." And they never, ever look convincing.

In the Farrelly Brothers' "Shallow Hal" (2001), Jack Black plays the titular role, a "No Fat Chicks" kinda guy who's hypnotized by self-help guru Tony Robbins into only seeing "inner beauty." Hal then falls in love with 300-pound Rosemary Shanahan (Gwyneth Paltrow), a social worker who, to Hal, looks like, well, Gwyneth Paltrow. The movie has its share of fat gags, certainly sending a mixed message. But what's more sinister is the cop-out casting of Paltrow as both Skinny and Fat Rosemary.

Almost every other character in the film that's viewed askew by Hal is played by two different people: a traditionally attractive actor and what we've come to call a "character actor" (a Hollywood euphemism that usually means "not good-looking enough for lead roles"). By burying Paltrow under latex and makeup, the film not only gives us an unconvincing obese girl, it lets the audience off the hook: We're not forced to truly deal with our attitudes toward obesity because we know Gwyneth the actress isn't fat. If Rosemary had been played by someone like, say, Camryn Manheim, the film would've carried far more weight (no pun intended).

Subconsciously or not, it's easier for the audience to laugh at the fat person if they know that the actor underneath is actually trim. Eddie Murphy in "The Nutty Professor" remakes; Julia Roberts in "America's Sweetheart"; Martin Lawrence in "Big Momma's House"; Kenan Thompson in "Fat Albert" — all make safe targets because they're not really fat. (OK, Thompson's not skinny, but he's certainly not "Hey, Hey, Hey" huge).

But to the overweight person sitting in the audience, the experience must be similar to a black person watching an old blackface minstrel show. When the character is presented as mean-spiritedly as Mike Myers' Fat Bastard character from the "Austin Powers" movies or scary-thin Courteney Cox-Arquette's Fat Monica from flashback episodes of "Friends," it becomes outright torture.

Some argue that the overweight differ from other victims of discrimination in that they made themselves fat; overeating and not exercising was their decision and they have to live with the consequences, including societal disapproval. And while that may be true in many (but by no means all) cases, few physical attributes invite more open scorn than a lot of extra pounds.

Orson Welles was arguably one of the most talented men to ever work in film. And yet in the final years of his life, he was better known (and mocked) for his great weight than for writing, directing and starring in "Citizen Kane." Similarly, Marlon Brando's body of work became irrelevant to many movie fans when he became the object of fat jokes. When Renée Zellweger plumped up to play Bridget Jones (twice), the celebrity press couldn't stop talking about how "brave" she was to pack on a whoppin' 25 pounds! On TV, while there are many things to ridicule Anna Nicole Smith about, the main source of viewer schadenfreude on her painful 2002 reality TV show was her weight gain. And Kirstie Alley's ill-fated Showtime sitcom, "Fat Actress," was a painfully schizophrenic showcase for the former "Cheers" star's tussle between self-loathing and pride. While the show was purportedly a satire on "lookism" and the shallowness of America in general, and Hollywood specifically, it usually played to the very shallowness it was mocking.

So, has there ever been an overweight lead character in a movie played by an overweight actor where the issue of size wasn't necessarily ignored, but did not define the part? Yep. The character was Tracy Turnblad, the actress was Ricki Lake and the movie was John Waters' 1988 musical tribute to '60s soul, "Hairspray." The picture of self-confidence, Tracy is immune to the weight-centric taunts of the evil, shallow Amber Von Tussle (Colleen Fitzpatrick), becomes the star of a Baltimore Dance Show and wins the heart of the hunky Link Larkin (Michael St. Gerard).

But (as with so many Waters characters) Tracy is a Hollywood rarity. The fact remains that we're far more likely to see "Fat Monica: The Motion Picture" than we are a somewhat zaftig Amazon suiting up as Wonder Woman.

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