The "Calories In Calories Out" Theory Makes Testable Predictions: What are They?

Calories In Calories Out: are they really all that matters? This is the conventional wisdom. As the Department of Health & Human Services' website clearly states in its dietary guidelines for Americans "A Healthier You":

"when it comes to calories and managing your weight... a calorie is a calorie is a calorie."[1]

KEY POINT: The Caloric Balance Hypothesis tells us that "a calorie is a calorie."

If you accept the assumptions behind the Caloric Balance Hypothesis, which we just discussed, logic compels you to agree with that statement.

Let’s look at some of the implications of this calories in calories out idea:

First of all, it tells us that the body is a simple machine, much like a bomb calorimeter or a car engine. It doesn’t matter whether you’re eating a calorie of protein, a calorie of fat, a calorie of carbohydrate, or a calorie of anything else. It’s calories that "count." Our fat tissue is essentially a piggy bank for calories. Weight control is a matter of simple accounting.

This theory also tells us that fats should be more fattening than carbohydrates and proteins. Fats, after all, have 9 calories per gram; whereas, carbs and proteins each only contain 4 calories per gram. If the only relevant factor is the NUMBER of calories eaten/burned, then the logic of "a calorie is a calorie is a calorie" forces us to concede that fats must be uniquely fattening.

Your fat tissue can't tell the difference between kinds of foods. The calories in calories out hypothesis very clearly says that your body "sees" the energy from different foods identically. You will get equally fat from:

• 890 calories of bacon fat
• 890 calories of high fructose corn syrup
• 890 calories of broccoli
• 890 calories of lean chicken
• 890 calories of cumin

This may sound silly. But there's no getting around it: according to the mainstream theory, only the number of calories, not the type, matters. All calories are created equal. And, by the way, if a defender of the calories in calories out hypothesis hedges and starts to argue that, "well, some calories may have different effects on your fat tissue than others," then he or she has abandoned the Caloric Balance Hypothesis. No hedging is allowed, according to the logic of the theory.

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