The logic and rationale of keeping track of your calorie count
seem believable, don't they? Of course they do. Unfortunately, calorie
counting would only be important if your body acted like a furnace, as
many diet gurus suggest. This is a very simple-minded suggestion that
does not apply to human biology.
Understanding the realities of calories and why they hardly matter for weight loss requires some explanation.
What Calories Really Are
A calorie is a unit of heat. Heat is not directly useful metabolically. Once a calorie is released, there is no putting it back. Heat can only dissipate.
Scientists have a very specific definition of a calorie. With some variation, the simplest way to say it is that a calorie is the amount of heat that is required to raise a cubic centimeter (milliliter) of water one degree Celsius, at room temperature and at sea level.
Saying that you can consume calories is like saying that you can eat heat.
Nutritionists, medical doctors, fitness trainers, and many other experts who should know better, incorrectly equate food calories to metabolism. This simple-minded reasoning goes something like this: The calories contained in the food you eat provide energy, in the form of calories, for you to live.
Now that you know what calories really are, you can understand that the only thing they can do is provide heat. They are important for maintaining body temperature, but that is all.
The Nonsense of Food Calories
Do you know how we measure calories in any food? We incinerate it in an instrument called a bomb calorimeter. When a substance is completely combusted, until nothing but the charred remains are left, it has released all of the calories that it contained. A bomb calorimeter measures how much heat is released upon complete combustion, which is expressed in calories.
Oh, by the way, the term 'calorie' commonly applies to two different quantities. One is the definition above (i.e., raising 1 cc of water 1 degree Celsius). The other is 1,000 times that amount - the amount of heat required to raise 1 liter (1,000 cc) of water 1 degree Celsius. Technically, to be clear about which is which, the small calorie is written with a lower case 'c' (calorie), and the larger calorie is written with an upper case 'C' (Calorie). You will also see Calories expressed as kilocalories (thousand calories).
One Calorie is therefore 1,000 calories, or one kilocalorie.
Regardless of how you label food, using 'calories' or 'Calories', it is nonsense to suggest that they provide you with nearly the amount of heat that they yield in a bomb calorimeter. The whole business of counting calories, as measured in a bomb calorimeter, has nothing to do with what happens to food when you eat it.
The main reason is that you can never, ever get all the energy out of food. At most you might get 10 to 20% of the potential energy that any food yields in a bomb calorimeter. Sometimes you won't get any calories at all.
At least a dozen factors determine the efficiency by which you actually harvest energy from any particular food at any particular time.
A Ridiculous Comparison
Consider this: in a calorimeter a gram of starch will yield the exact same number of calories as a gram of cellulose, which is indigestible fiber. As you and I both know, starch is a source of food calories for people. In contrast, cellulose is not.
This means that a calorimeter will get the same number of calories from equivalent amounts of carbs from potato as from celery. Obviously, your body couldn't possibly do that.
What's Really Important About Food
Instead of comparing the metabolism of food to a furnace or calorimeter, it is much more meaningful to talk about what happens to different foods when they are digested, how they get into different kinds of cells (e.g., fat vs. muscle), and what happens to them once they are there.
For a surprising example of what this means, let's compare digestion of the two nearly identical sugars, glucose and fructose. Following their metabolic fate is much more meaningful regarding their roles in diet than just keeping track of their calorie count. In fact, these two sugars have identical caloric potential - 4 Calories per gram. However, glucose goes into many different tissues - most notably muscle and brain - and intact fructose never escapes your liver.
The consequences of these differences are that glucose serves the metabolism of your entire body, whereas fructose has to be converted to something else before you can do anything with it. That something else is largely fat. In simpler terms, fructose will make you fat much faster than glucose will. This is why one of the biggest problems with consuming foods that contain high-fructose corn syrup is that they are highly fattening.
By the way, once you understand what is truly important about foods of all kinds, which is clearly not their calorie content, you will be very clear on why calories have nothing to do with obesity. Chew on that comment for a while (pardon the pun), because this is the kind of thinking that will guide you to success in any weight loss or fitness program that works for a lifetime.
.
Understanding the realities of calories and why they hardly matter for weight loss requires some explanation.
What Calories Really Are
A calorie is a unit of heat. Heat is not directly useful metabolically. Once a calorie is released, there is no putting it back. Heat can only dissipate.
Scientists have a very specific definition of a calorie. With some variation, the simplest way to say it is that a calorie is the amount of heat that is required to raise a cubic centimeter (milliliter) of water one degree Celsius, at room temperature and at sea level.
Saying that you can consume calories is like saying that you can eat heat.
Nutritionists, medical doctors, fitness trainers, and many other experts who should know better, incorrectly equate food calories to metabolism. This simple-minded reasoning goes something like this: The calories contained in the food you eat provide energy, in the form of calories, for you to live.
Now that you know what calories really are, you can understand that the only thing they can do is provide heat. They are important for maintaining body temperature, but that is all.
The Nonsense of Food Calories
Do you know how we measure calories in any food? We incinerate it in an instrument called a bomb calorimeter. When a substance is completely combusted, until nothing but the charred remains are left, it has released all of the calories that it contained. A bomb calorimeter measures how much heat is released upon complete combustion, which is expressed in calories.
Oh, by the way, the term 'calorie' commonly applies to two different quantities. One is the definition above (i.e., raising 1 cc of water 1 degree Celsius). The other is 1,000 times that amount - the amount of heat required to raise 1 liter (1,000 cc) of water 1 degree Celsius. Technically, to be clear about which is which, the small calorie is written with a lower case 'c' (calorie), and the larger calorie is written with an upper case 'C' (Calorie). You will also see Calories expressed as kilocalories (thousand calories).
One Calorie is therefore 1,000 calories, or one kilocalorie.
Regardless of how you label food, using 'calories' or 'Calories', it is nonsense to suggest that they provide you with nearly the amount of heat that they yield in a bomb calorimeter. The whole business of counting calories, as measured in a bomb calorimeter, has nothing to do with what happens to food when you eat it.
The main reason is that you can never, ever get all the energy out of food. At most you might get 10 to 20% of the potential energy that any food yields in a bomb calorimeter. Sometimes you won't get any calories at all.
At least a dozen factors determine the efficiency by which you actually harvest energy from any particular food at any particular time.
A Ridiculous Comparison
Consider this: in a calorimeter a gram of starch will yield the exact same number of calories as a gram of cellulose, which is indigestible fiber. As you and I both know, starch is a source of food calories for people. In contrast, cellulose is not.
This means that a calorimeter will get the same number of calories from equivalent amounts of carbs from potato as from celery. Obviously, your body couldn't possibly do that.
What's Really Important About Food
Instead of comparing the metabolism of food to a furnace or calorimeter, it is much more meaningful to talk about what happens to different foods when they are digested, how they get into different kinds of cells (e.g., fat vs. muscle), and what happens to them once they are there.
For a surprising example of what this means, let's compare digestion of the two nearly identical sugars, glucose and fructose. Following their metabolic fate is much more meaningful regarding their roles in diet than just keeping track of their calorie count. In fact, these two sugars have identical caloric potential - 4 Calories per gram. However, glucose goes into many different tissues - most notably muscle and brain - and intact fructose never escapes your liver.
The consequences of these differences are that glucose serves the metabolism of your entire body, whereas fructose has to be converted to something else before you can do anything with it. That something else is largely fat. In simpler terms, fructose will make you fat much faster than glucose will. This is why one of the biggest problems with consuming foods that contain high-fructose corn syrup is that they are highly fattening.
By the way, once you understand what is truly important about foods of all kinds, which is clearly not their calorie content, you will be very clear on why calories have nothing to do with obesity. Chew on that comment for a while (pardon the pun), because this is the kind of thinking that will guide you to success in any weight loss or fitness program that works for a lifetime.
.
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