October 16, 2004
Q: Is all fiber nondigestible and, therefore, produce no calories? - Layperson
A: There are two types of fiber, insoluble (i.e.-cellulose, hemicellulose, lignin, and whole grains) and soluble (i.e.-gums and mucilages, and pectins). The insoluble type is not dissolvable in water or metabolized by the large intestine bacteria, so is not digestible for these reasons. The soluble type is dissolvable in water and is metabolized by the large intestine bacteria to form short chain fatty acids and gases and is digestible and absorbed into the bloodstream, yielding approximately 3 kilocalories/gram. Since most people consume diets containing both types of fiber, calories are being produced.
Q: What is the "glycemic index" and what is it used for? - Layperson
A: The "glycemic index" is a measurement of how high 50 grams of carbohydrate from different foods will raise the blood sugar (measured in milligrams/deciliter of blood) using the arbitrary number 100 as a reference point for white bread or if glucose is used, then glucose's reference point would be 100 and white bread would be 140. If glucose=100 as the reference point, than in any chart using white bread=100 as the reference, you would have to convert the numbers by dividing by 1.4. Using white bread=100 as the reference point, foods with numbers below 100 convert to sugar slower than white bread and those foods with numbers higher than white bread, convert to sugar faster than white bread. Starchy foods such as carrots, rice, and potatoes and foods high in sugar such as candy, honey, and maple syrup, have high indexes because they raise blood sugar rapidly. High fiber foods such as All-Bran cereal and whole-grain rye bread have low indexes because they raise blood sugar slowly. Any number of factors can alter these indexes - individual differences, the way the food is processed, the fat, fiber, and protein content of the foods, and so on. The "glycemic index" is a good aide in preparing diabetic diets, weight control, preparation for athletic events, however, it should not be the sole factor. Other factors such as the nutritional content and amount of food consumed, the level of physical activity, and the fitness level of the individual should also be considered.
DISCLAIMER: The information in this column, is NOT intended to diagnose and/or treat any health related issues and is provided solely for informational purposes only. Consult the appropriate healthcare professional before making any changes to your healthcare regime. Even what may seem like simple changes in the diet for example, can interact with, and alter, the efficiency of medications and/or the body's response to the medications. Many herbs and supplements exert powerful medicinal effects. Neither the author, nor the website designers, assume any responsibility for the reader's use or misuse of this information.