The film opens with a fetching redhead puffing away on a treadmill. She's perspiring, but she's smiling gamely into the camera.
"It's not an average workout, but I wasn't an average weight," she explains. "I have to do above and beyond what any of you guys would have to do. I have to try twice as hard, sometimes three times as hard -- just to maintain this level of ... chubbiness."
And she is right. She is chubby. By 21st century mainstream (and magazine) standards of beauty, this young woman is probably 30 pounds overweight. The dimples, the ponytail, the strawberries-and-cream complexion and the undeniable on-camera charisma make her very appealing. But there is no doubt that most physicians would urge her to lose weight.
Later in the film, we learn that she exercises three hours a day. And when her mother was dying of cancer, this thirtysomething nursed her and learned a great deal about nutrition. Dedicated and determined, she eats healthy meals and sticks to a strict exercise regime. Why, then, is she "chubby?"
Doctors don't know. That is one of the first things you learn in Fat: What No One is Telling You, a 2007 documentary that is, by turns, entertaining, moving and eye-opening. (The PBS home video, directed by Andrew Fredericks, can be rented on www.netflix.com or purchased on www.amazon.com).
The questions are endless, a narrator tells the audience. "Is it her genes, her childhood, a flaw in her character, stress, sadness, a lost love, processed food, television, seductive advertising, lack of sleep, a government that subsidizes corn, sugar and beef?"
All of the above may well contribute. But taken together, they still don't constitute an answer. Doctors cannot help the vast majority of obese people lose weight -- and keep it off -- because doctors don't know what causes obesity.
"If It Were That Simple…"
Although many physicians still "believe that obesity is caused by eating too much and not exercising enough, such thinking is too simplistic," says Dr. Robert Lustig, of the Division of Pediatric Endocrinology at the University of California, San Francisco. An expert in the field, he knows that obesity is "a chronic condition." And we don't have a cure.
This is why, even when patients enter medically supervised weight-loss programs and stick with the rules, Lustig explains, 95 percent regain whatever pounds they lose.
"This is not simply ‘energy in and energy out.' If it were, we would have solved it a long time ago," says Harvard's Dr. Lee Kaplan, who heads the Weight Reduction Program at Massachusetts General Hospital and has established a new, comprehensive basic and clinical research program.
"Obesity doesn't seem like a subtle disease ," adds Kaplan, who appears in the documentary. "But it is. If something is off kilter by just 1 percent in your system, that can lead to a 100-pound weight gain . More than 400 genes are involved in weight regulation. And that doesn't include the environmental factors."
Fat goes on to introduce us to a very bright 300-pound 18-year-old who has sought medical help, researched obesity and, with the support of his doctor, is now planning on bariatric surgery (a.k.a. "stomach-stapling"). "They just haven't figured out this obesity thing," he says. "There is something haywire in your body.
"You become depressed when you realize that … you're going to die earlier. And when they bury you, they'll need 20 people to carry you rather than four."