Study: 'Weight-ism' More Widespread Than Racism

The social current driving this is the obvious fact that no one is responsible for his or her race, or gender or even age. That's a given. But the traditional thinking goes that people should be able to control their weight, so if they're obese, it's their fault.

But that, according to Puhl, is dead wrong.

"We place a lot of emphasis on personal responsibility for body weight," she said. "Our billion-dollar diet industry is founded on that premise. Your weight is modifiable. But that does not reflect the current state of science. We know from hundreds of randomized clinically controlled trials that it's very difficult to sustain weight loss over time with our existing treatment methods."

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"That has compelled a number of expert panels, like the National Institutes of Health, to conclude that we really can't expect you to lose more than 10 percent of your body weight and be able to keep that off."

For a 300-pound man, she notes, that's a mere 30 pounds, and he's still overweight, unless he's nearly seven feet tall. Obesity is based on the body mass index (BMI) that is derived from a formula based on weight vs. height. Normal BMI is 18.5 to 24.9. Obesity begins at BMI 30 and ranges up to 40.

Puhl emphasized that she isn't saying people shouldn't try to control their weight. Scores of studies have shown that excess weight contributes to a wide range of diseases, and physical fitness is one of our best bets for fighting everything from heart attacks to aging. But let's face it, if diets worked, we would all be skinny. Many uncontrollable factors contribute to obesity, like genetics and some diseases, yet we still blame the individual.

The heart of the problem, Puhl said, is that obesity brings social stigmatism and stereotyping, and that can lead to depression, discrimination and binge eating, so the problem just gets worse.

But why are we failing so miserably at keeping our weight under control?

"We live in a very toxic food environment," Puhl said. "We make it very easy for people to be unhealthy. Unhealthy foods, or junk foods, are accessible, cheap and engineered to taste very, very good. Healthy foods, like produce, are not as accessible, and are more expensive."