Americans are fat because they trust what they've been told about eating.
Anyone see the new dietary guidelines?
Eat less, they say, and you will lose weight. They also tell us to eat more fruits and vegetables and to cut back on the salt, red meat, cream and butter.
Yawn. If these latest rules for healthy eating sound like a bunch of warmed-over same-old, that's because they are.
Obesity may pose the most daunting health problem of our time, but you wouldn't know that from the tepid updating of the guidelines released on Monday.
It is a low-fat, low-salt, low-calorie message. Some observers have been excited to report that the guidelines are finally telling us to "eat less."
But these are essentially the written version of the offerings in the food line at Mayo Clinic's Healthy Living Center, a fat- and calorie-focused plate line just footsteps away from where I sit writing this very sentence.
And it isn't going to work.
If telling people to eat fewer calories and less saturated fat were an effective way to stem the tide of obesity, we'd all look like Jack LaLanne, who died the other week. LaLanne took with him a certain maturity about human nature that seems sadly missing in the nutrition sciences community.
According to his obituary, LaLanne had a friend who chain-smoked, drank a quart of whiskey every day and weighed 300 pounds. LaLanne would light his cigarettes for him.
"This bull about changing people," he said, "you never change people. Accept 'em, accept 'em, accept 'em."
It's hard to imagine that spirit at work within the army of nutritionists marching forward with the latest guidelines. They believe losing weight is a matter of willpower.
How do we know this?
Well, if you have been delivering the same message for four decades, and it hasn't worked, the only explanation that can justify keeping the same message going is that you believe the problem lies in the poor willpower of fat people to follow your instructions, not the poor science behind the instructions themselves.
But as the award-winning science writer Gary Taubes explains in his new book "Why We Get Fat: And What to do About It," the message hasn't worked because the science of fat storage and the history of obesity research tell us quite clearly that the message is wrong.
Taubes, who spoke at the University of Minnesota recently, has waged a lonely campaign to document the contradictory nature of dietary science and the recommendations that ensue.
As the author of the "What if it's all Been a Big Fat Lie?" -- a much-talked-about New York Times magazine cover story in 2001 -- and then the 2007 book "Good Calories, Bad Calories," Taubes has made a compelling case that we become fat, diabetic and sclerotic because of too many carbohydrates, not too much saturated fat, too many calories, too little exercise or willpower.
His latest book specifically takes on the idea that managing one's weight is a simple matter of burning more calories than you consume. Calories-in, calories-out, he argues, "tells us nothing about why this happens, why we consume more calories than we expend."
As he points out, "a logician would say that it contains no causal information."
That causal information -- the reason a person would ever consume more calories than he expended, Taubes says -- is because carbohydrates in the diet cause our bodies to release the hormone insulin, and this insulin causes energy to be deposited as fat that cannot be burned as long as the insulin keeps flowing.
That leaves us hungry, and quixotically, still fat. In other words, fat people are not overfed; rather, they are malnourished.
But it gets worse. Insulin not only leaves us fat and hungry, it leaves us hungry for more of the food causing the problem -- carbohydrates.
To the extent we eat fewer carbohydrates in the process, eating less may eventually make us lose weight, Taubes says. But as a blanket rule, telling us to eat less will simply cause us to have less energy, and that is going to cause us to move less and burn fewer calories.
It's why diets that tell people to cut calories rarely work over the long term.
Telling us to cut back on saturated fat is equally outdated. It invites us to replace it with processed "low-fat" foods that are high in carbohydrates.
Also, it is based on the outdated idea that saturated fat in the diet leads to heart disease.
As a meta-analysis published last January in the American Journal of Clinical Nutrition reported, "there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease or cardiovascular disease."
Perhaps the authors of the new guidelines did not read those studies. Worse, perhaps they did. What would it have taken for them to tell us the truth, that the rise in obesity in this country has been elicited by the advice to count calories and cut fat from the diet?
The eating of a food not mentioned in the new guidelines. Crow.
Paul John Scott is an award-winning Rochester-based health writer.
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