Sunday, May 30, 2010
MY CURRENT OPINION ON THE ROLE OF CALORIES IN THE HUMAN BODY
There is plenty of evidence, and I don't think this is news to anyone, that the macronutrient called carbohydrate is dealt with in the body by the release of insulin, the "fat-storing" hormone. We know that each person's body has a certain amount of carbs that can be eaten without excess insulin being released that will want to store the excess carbs as fat in the fat cells. Added to that is the fact that some carbs cause a rapid rise in blood sugar (blood glucose). These "high glycemic index" carbs should be limited or avoided all together in favor of "low glycemic index" carbs, which do not cause that spike, but keep blood sugar more stable and balanced. Through trial and error, possibly starting at a low level of low glycemic index carbs, a person must discover the quantity of carb grams that can be tolerated in his or her own body, in order to lose or maintain body fat.
So knowing how much carbohydrate to eat is a good thing to know. Carbohydrates are measured in grams, and a gram of carbohydrate contains 4 "calories" in a lab, but so what? Why take the extra step of converting the carbs you know you can eat into another number that has no bearing in your body?
Protein is the next macronutrient that the body utilizes. Protein, in a general sense, is used to rebuild muscle and other tissues in the body. Although it is not used primarily as "fuel" to move us around or run our bodily systems, it is possible to overeat protein, just as it is possible to overeat carbs. When more protein is consumed than is needed by the body, the excess is converted to glucose and then stored as fat.
Although it's a a guessing game how many grams of carbs you can eat and lose or maintain body fat, and there is no "chart" that you can look at, punch in your age and height and know for sure how much of this macronutrient you can eat, protein may be a little easier to figure out. There are charts and computations you can use to get you in the right neighborhood of how many grams of protein to eat. Here are some of the computations I have seen:
1. If you have had your body composition tested by any of a few different methods (right click here to see what your choices are), you can multiply your pounds of lean body mass (your total weight minus your pounds of body fat) and multiply that number by 0.5 to 1.0, depending on your level of activity. This is the method Mark Sisson uses in his book The Primal Blueprint. Example: A sedentary person weighing 150 pounds with 75% lean body mass (LBM) would have 112.5 pounds of LBM, and multiplied by 0.5, they should, at a minimum, be eating around 56 grams of protein per day. At the opposite end of the spectrum, if they are extremely active, they would multiply their LBM by 1.0 to equal around 113 grams per day.
2. Another method I have seen on the Atkins website is to take your total goal body weight and multiply it by 0.7 to 0.9, again, depending on your level of activity. Using this math, the 150 pound sedentary person, assuming they wanted to lose another 20 pounds, would multiply their goal weight of 130 by 0.7 and aim for 91 grams of protein per day, or if they are extremely active, by 0.9 and aim for 117 grams per day.
It is your choice which method you decide to try. Or you may decide to split the difference and see how you do. In either case, settling on a optimum quantity of grams of protein will be your goal.
So knowing how much protein to eat is also a good thing to know. Protein is measured in grams, and a gram of protein contains 4 calories in a lab, but, again, so what? Why take the extra step of converting the protein you know you can eat into another number that has no bearing in your body?
Finally, we have the macronutrient fat. I have really been on a quest these past several weeks to find out what happens if we eat excess fat, more than our bodies need for "fuel". There are many opinions on the subject, and I'm going to try to write about that soon. For right now, it will have to suffice to say that I do believe, based on what I have been learning, that it is possible to overeat fat as well as protein and carbs. So part of what you will be learning about how your body runs best is how many grams of fat you can eat and either lose or maintain your body fat.
So knowing how much fat to eat is a crucial thing to know. Fat is measured in grams, and a gram of fat contains 9 calories in a lab, but, at the risk of stating the obvious and repeating myself, so what? Why take the extra step of converting the fat you know you can eat into another number that has no bearing in your body?
As I see it, it is important to experiment with your food intake so that you can discern how many grams of carbs, protein and fat is best for your weight loss goals. And keep in mind that this will not be a static set of numbers, but can and will change in time as your body composition changes, as your hormone levels change, as you level of activity changes and a host of other reasons.
CALORIES IN CALORIES OUT?
Here is the problem with calories, as I see it: There are no end of charts and graphs that will tell you how many "calories" to eat to lose or maintain your weight. These charts do not take into account the breakdown of the macronutrients you are consuming - the carbs, protein and fat. They maintain that "a calorie is a calorie" and that if you eat a certain amount of calories, regardless of the macronutrient makeup, you will maintain your weight, and if you cut out 500 calories per day, in a week you will lose one pound, because 3,500 calories equals one pound. Right? Hmmm... So, it makes no difference if you eat all fat, or all protein or all carbs, because a calorie is a calorie. This view does not take into account that eating all carbs would cause massive spikes in blood sugar, and fat would be stored, where if you were eating all protein or all fat, this mechanism would not be triggered. This view does not even consider the "metabolic advantage" of eating low carb and high fat. So a calorie is not a calorie, and that belief is bunk, if you ask me. Not to mention that if a person has imbalanced hormones, such as thyroid, which regulates metabolism, all bets are off, and a person may be unable to lose any weight at all eating the "proper" amount of calories, or may even gain weight eating what they "should".
The other side of the "calorie coin" is that there is no way to know how many "calories" are being burned by doing certain activities. You can also find charts in abundance that will tell you that if you weigh 150 pounds and run at 4 miles per hour for 60 minutes, you will "burn off" 562 calories. These numbers are apparently based on eating a low fat, high carb diet. But what about the metabolic advantage? And even if that could be factored in, is it valid? Do not different people have different metabolisms? We all know slim people who seem to be able to eat whatever they want and do not exercise, and yet, they never gain weight. How does "Calories In Calories Out" apply to them? And on the other extreme, what about the people who are overweight, and no amount of restricting calories or excessive exercise will cause them to lose weight? And more to the point, is a calorie even a valid unit of measurement when talking about how the body uses the food we consume to help us jump around or lift heavy things?
I've said it before and I'll say it again - If a calorie is a calorie, then you should be able to put two people in a room, and feed them the same thing and have them do the same exercise, and they should lose the identical amount of weight. But they wouldn't, would they?
To tell people to eat a certain amount of calories and do a certain amount of exercise to lose weight is a recipe for disaster at the most and failure at the least. We should be showing people how to figure out how many grams of each macronutrient to eat, not telling them to count calories and do chronic cardio (to quote Mark Sisson) to lose weight.
Should we eat the right amount of food in the right proportions, and should we exercise in some way? Absolutely! But until people understand the reasons we are overweight to begin with, counting calories and exercising are not going to keep people from getting fat.
On a person note, although I have used the term "calories" to chart how much I eat, because it is a term everyone thinks they understand, I'm going to stop, starting today. From now on, I will report my food using the number of grams of fat, protein and carbs. I never have tried to estimate how many "calories" I am burning when I exercise, so no change there!