Is a calorie a calorie or what apes can teach us

The debate has been raging on between opposite schools of thought since the word fitness was invented: is a calorie a calorie? In other words is the energy measure "Kcal" a purely fungible notion as physicists (and I) are inclined to believe or are "Kcal" (more often referred to as simply "calories") not born equal depending on what they consist in? (low-glycemic starch, high-glycemic sugar, lipids, protein...).

IS A CALORIE A CALORIE?
The definitive solution to this quandary would have dramatic consequences on the efficiency on just about any diet. If all Kcal are created equal, then the only relevant metric to lose weight is the number of Kcal consumed daily minus the daily energy outlay (basic metabolism + physical activity) If on the other hand, there are "good" and "bad" Kcal then the latter metric will be skewed and designing a diet will be a much more complicated affair.

I must point out a caveat at this point: even if the former theory turns out to be true, this does not give anybody a license to eat 80% of their Kcal in the form of fat, even though the bottom line may be a weight loss. Those who believe they can are probably believers of the nefarious Atkins diet (this guy died of a heart attack for crying out loud!).

OUR SIMIAN COUSINS CAN'T CHEAT
Back to our original debate: because people in clinical trials (let alone your neighbor) are notorious for grossly underreporting what they eat on a daily basis, the idea occurred a long time ago to scientist to use our closest cousins the apes. They cannot tell you what they have eaten for breakfast, but because they are apes, they can be kept in a controlled environment (the PETA people would call it a cage) and, as a result, their food intake can be monitored with extreme accuracy.

THE JURY IS STILL OUT ON THE CALORIE QUANDARY
Now a recent article in the New York Times sheds a not-altogether-new light on this debate. In this article Dr Barbara C. Hansen a protagonist in this debate makes this most important remark: "Fat Albert, one of her monkeys who she said was at one time the world’s heaviest rhesus, at 70 pounds, ate nothing but an American Heart Association-recommended diet,” whereas her contradictor Anthony G. Comuzzie claims: “It wasn’t until we added those carbs (high-fructose corn syrup) that we got all those other changes, including those changes in body fat”

MY OPINION ON CALORIES
Whom to believe? Even though my major in college was Math and Physics I make no claim of being a scientist . So I will only found my opinion on my 20-year experience dealing with fat individuals (and keeping my body weight rigorously unchanged over the same period). I would definitely side with Dr Hansen. My opinion is that only the number of calories (Kcal) ingested counts for predicting weight changes in individual of all ages. And once again I will point out that this rule is irrelevant for describing how healthy a particular diet is (see the above "caveat").

In a nutshell, all that is required if you want to lose weight is decreasing the number of calories you take in daily, provided your level of activity does not change. By sticking to this simple principle long enough you will unfailingly succeed in losing weight but you may not become any healthier in the process (particularly if your calorie restriction is indiscriminate).

SOMETIMES THE TRUTH IS JUST NOT PROFITABLE ENOUGH
So why all the theorizing about good and bad calories, pineapple diets and other catchy formulae? I am afraid this is all about clever marketing and generating profits for the countless Atkins of the world. Weight loss is a $60 billion (!!) industry in the US. I doubt anybody is going to make any money telling overweight baby- boomers that all they need to do to lose weight is buying a $20 food scale and counting their daily calorie intake.