This week's root of all evil
I am tired of all discussions about diet and exercise. Part of the problem for me is that the math is so incredibly imprecise. We are told over and over that weight gain = calories consumed – calories burned, 1 pound = 3500 calories. If it were so easy, Weight Watchers would not have had revenues of $1.4 billion in 2009.
There’s a catch, and that is that the body’s metabolism adjusts to a given weight level. The rate of calorie burn can vary, which also means that the rate of weight loss can vary. Are you burning 100 calories per mile when you run, or only 75?
We know that people do have weight problems, and that losing weight and keeping it off is very, very hard. And we also know that the advice we get from Those Who Know changes all the time. I remember when butter was bad and margarine was good, the ideal diet was high in carbohydrates and low in protein, and a peanut butter sandwich and a glass of apple juice made a fine snack for a toddler.
Now? Butter is good! Protein is better! No nuts for children under six, and juice is as bad as pop!
And that’s saying a lot, because pop, it seems, is more sinful than whiskey because it is made with high-fructose corn syrup. (In defense of my state’s many corn growers, I should point out that high-fructose has more fructose than regular corn syrup, and that the extra fructose is added to give it the same fructose levels, and the same calories, as cane sugar.)
In March, researchers at Princeton University announced research showing that rats that ate high-fructose corn syrup gained more weight than rats that ate cane sugar. If the study holds, then it shows that some calories are harder to burn than others. We already know that the body burns calories at different rates over time because of metabolic changes. But if 100 calories from sugar burn at a different rate than 100 calories from high-fructose corn syrup, then we have something more complicated than how many miles one would have to run to burn 100 calories. Hence, it is time to retire the weight gain = calories consumed – calories burned, 1 pound = 3500 calories equation forever. That won’t be the way that the story is reported, though, because no nutrition story is critical of the research. From a scientific perspective, the Princeton studies need to be duplicated. Then, if high-fructose corn syrup does metabolize differently than cane sugar, someone needs to start figuring out why. Instead, though, every woman’s magazine will have a story in the next six months about the evils of high-fructose corn syrup. There will be a lot of hysteria, and then in five years, we’ll find out that maybe the study didn’t hold or that maybe high-fructose corn syrup is actually good for you.
I’m not defending high-fructose corn syrup, but I don’t like equations with unknown rates of change in them. Nutritional research and reporting follows a very predictable pattern because no one knows anything. Compounding the problem is that we have confused weight with beauty, health, intelligence, long life, and morality. (Overweight people actually live longer than others, believe it or not. Or at least, that’s what the research shows for now. )
I’d like it if we did know something. I’d like to see real evidence that has stood up to repeated clinical trials, along with a real understanding of what the rate of change is on calorie burn and retention. I doubt we’ll see it any time soon, though, if only because it is so difficult to do any sort of controlled study on human beings. The only solution, then, is Aristotle’s dictum, “moderation in all things.”
By the way, I am clairvoyant, and so I already know that the first six comments will look like this:
Fat people are lazy and stupid! I exercise every day and I watch what I eat! It’s not hard, people! If you can’t figure it out, you deserve to be ugly and die!
Please, prove me wrong.
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