I have several problems with calorie counting as a method of weight loss. Even if this weren’t a growing trend, it simply doesn’t make any sense. There are some simple logical reasons why it just doesn’t add up.
1) A calorie is a measurement of energy, not mass.
While Einstein may have equated the two, that equation does not apply here. Simply, calories are how well does an object burn, but your body isn’t a simple furnace, and can only use certain components as energy. At best we might consider the calories of only applicable substances, but we don’t track that.
Current wisdom says that a 3500 calories equals a pound of body fat. If that’s the case, a huge thanksgiving feast eaten over the course of a day that totaled 14 thousand calories would mean you gained exactly 4 pounds by the time you finished digesting. This means that you have to run 4 marathons to lose those 4 pounds (at an average of 3500 calories burned per marathon). Weigh yourself a day or two later (after eating and eliminating normally) and you’ll see you’re back to your normal weight. You do not gain a weight proportionately to the calories you eat.
As an example, a log that has 1000 calories of energy cannot be digested, where 1000 calories of sugar can. If one might argue “a log is all fiber”, consider that 1000 calories of coal, with no fiber, is indigestible too, but has the same amount of energy.
Further, 3500 calories of jet fuel is not a pound of mass. If it were possible to consume this as a food, there is no way your body could gain a pound from it. The mass is just not there!
2) Your body cares about the components of your food, not calories.
What you eat is more important than the calorie count of the food. Your body gains fat only by consuming certain molecules that get shuttled into your fat cells. Those molecules are triglycerides which the body makes from sugars. These triglycerides are shuttled there by insulin, which in turn may shuttle the triglycerides to muscle cells for energy if the right hormones are in place.
Your body does not use fat to make fat however. There are many types of fats, but your body only wants certain fats in its cells. Most consumed fats get used in cell building or hormone like functions in the body. Consumed fat is precious and the body doesn’t waste it for storing energy, as is popularly believed.
This means that if you eat 3500 calories of fat, you won’t gain a single pound; studies show you’ll actually lose weight eating nothing but fat. This also applies with eating protein; your body can make sugars out of protein but it’s very expensive so it avoids this unless necessary. The only thing your body can use to gain fat are carbs.
3) People have different metabolisms
Have you ever noticed how some people can eat pizza after pizza without gaining a pound, but others can look at cake and gain a size? This is simple different people’s bodies use their consumed food in different ways depending on health, fitness and age. If calories were truly a good measure of anything, we could predict weight loss regardless of metabolisms.
So there you have it. Three common sense reasons based on common science, physics, chemistry, and biology respectively, that thinking about calories is an absolute waste of time.