CHAPTER ONE:
EFFECTIVE WEIGHT MANAGEMENT TWO POWERFUL DIETARY PRINCIPLES
Two of the most powerful principles in effective weight management are to eat foods with a lower energy density and to eat foods with a lower glycemic impact.
(1) ENERGY DENSITY There are two ways to reduce calories. One is to eat less food. This way seldom works. Another way is to eat food with a lower energy or calorie density per serving. If we can increase the weight of food while maintaining the same level of calories, we can feel full and satisfied even during a period of weight loss. Fat has nine calories per gram while protein and carbohydrates have four calories per gram. The less fat in our diet, the lower the energy density. Fiber has two calories or less per gram. Water has no caloric value. Therefore, the more fiber and water in our food choices, the lower the energy density.
Dr. Barbara Rolls of Pennsylvania State University developed a way to measure energy density. This is described in her books "The Volumetrics Weight Control Plan" and "The Volumetrics Eating Plan". The calculation is performed by dividing the calories in a serving by the weight in grams. A number ranging from zero to nine is produced. The maximum energy density is nine because, as mentioned, pure fat has nine calories per gram. All other foods will have a lesser value. For example, raisins have an energy density of three. This means that there are three calories per gram in a serving of raisins. Strawberries, on the other hand, only have an energy density of .20. This means that there is only one fifth calorie for each gram of strawberries. Looking at this a different way, fifteen grams of strawberries has the same calories as one gram of raisins. Obviously, the strawberries would satisfy our hunger with far fewer calories. Eating foods with lower energy densities can satisfy our hunger without weight gain.
(2) GLYCEMIC IMPACT Glycemic impact refers to the twin principles of the glycemic index (GI) and glycemic load (GL). The glycemic index was first conceived of by Dr. David Jenkins and Dr. Thomas Wolever of the University of Toronto. It was expanded by Dr. Jennie Brand-Miller and her associates at the University of Sydney. The best description is the book "The New Glucose Revolution - The Authoritative Guide to the Glycemic Index". The glycemic index measures how rapidly carbohydrate foods are digested, converted to glucose, and cause blood sugars to rise. Pure glucose is given the maximum value of one hundred. All other foods are compared against glucose.
The hormone insulin, which is produced by the pancreas, is necessary to move blood sugar into our muscle cells where it can be used for energy. It is the nature of insulin to move the blood sugar into these cells as rapidly as possible. When our blood sugar drops back down to its baseline level, it is a signal that it is time to eat again. On the other hand, carbohydrate foods that are digested slowly cause a slower rise in blood sugar and its accompanying insulin response. This leaves us feeling more satisfied over a longer period of time.
The glycemic load was developed by researchers at Harvard University. It applies the glycemic index to specific servings sizes. . . . High glycemic index foods do not need to be avoided altogether. Many contain valuable nutrients. The glycemic load gives us a way of monitoring the glycemic response from these higher glycemic index foods.
GLYCEMIC DENSITY Is there a way of combining energy density and glycemic impact? I developed an approach to this synthesis which I called Glycemic Density (GD). . . . My previous book "Glycemic Density - Continuing the Glucose Revolution" used carbohydrate calories as a basis of calculation. I did this because I came at it from the direction of energy density. I took the carbohydrate calories per gram and multiplied it by the glycemic index (expressed as a decimal) to come up with the result. This . . . yielded a value which ranged from zero to four. A value of four would be pure glucose. Now, instead of carbohydrate calories, I have decided to use carbohydrate grams as a basis of calculation. This will yield a result that is one fourth of the prior value. The value range is now zero to one. Pure glucose would have a value of one.
Glycemic Density = (Net-Carbohydrate-Grams * Glycemic-Index / 100). / Total-Grams-in-Serving)
The reason for this change is that the first part of the formula is also the formula for glycemic load. To calculate the glycemic density, all that is needed is to divide the total glycemic load in the serving by the total grams. Since this is already listed in many instances, it will make our calculations much simpler. The glycemic density now becomes equal to the glycemic load in a gram of food.
INTRODUCING THE GLYCEMIC MATRIX This book introduces a further refinement of the glycemic index and glycemic density principles. The glycemic density and glycemic index represent the two ways that hunger can be satisfied. Glycemic density deals with the weight volume of food contained in a serving, while the glycemic index deals with how rapidly the foods are digested and metabolized into blood sugar. So I came up with the [graphical scheme] . . . which I call the Glycemic Matrix.
The foods in the upper left corner are those that would have the lowest impact on blood sugar levels along with the most bulk satisfaction. They will satisfy hunger the most, both in the short term and in the long term. The foods in the lower right corner are those that would have the highest impact on blood sugar levels along with the least bulk satisfaction. They will satisfy short term and long term hunger the least.
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