Glycemic Index

glycemic index

The glycemic index is a system in which a number is given to a particular carbohydrate food to determine how quickly or slowly the food breaks down into sugar in the bloodstream. This number is important since people tend to consume many high-glycemic index foods – refined carbohydrates (white pasta, white bread, white rice) that turn quickly into glucose (sugar) in our bodies. These foods do not sustain your appetite or energy (blood sugar) level and people end up overeating them.

If you incorporate low-glycemic index foods (foods that turn into sugar slowly), you can sustain a more even energy level and you also will not get hungry very quickly. This is due to non-fluctuating blood sugar. You know that sugar equals energy. When you eat refined or high-glycemic index foods, your blood sugar quickly climbs and then drops. When the blood sugar drops, you feel hungry since your brain signals your body to eat in order to maintain your energy level. However, if you consume mostly low-glycemic index foods, your blood sugar tends to level out and not fluctuate. This results in diminished appetite and a more sustained level of energy! In addition, by metabolizing sugar more slowly and over a longer period of time we have a chance to utilize the sugar or glucose before it gets stored as fat (triglycerides)!

Glycemic Load is a newer and more accurate term. The glycemic index (GI) tells you how rapidly a particular carbohydrate turns into sugar. It does not tell you how much of that carbohydrate in grams is in a serving of food. The Glycemic Load (GL) is the amount of carbohydrate grams in a food multiplied by the GI of that carbohydrate.

You can use the numbers in the charts as a guide. There are many influential variables when dealing with GI or GL. Combinations of food, and how you cook them can change the glycemic index/glycemic load. Since fat, protein, and high-fiber foods digest more slowly, by adding either one to a carbohydrate, the rate of absorption and consequently the glycemic index number will be changed. For example, Cornflakes alone have a high glycemic index number. Combining nuts with the cereal (high fat) will alter the digestion of the cereal (slow it down) and the glycemic index number will lower.

The following numbers were taken from The New Glucose Revolution by Jennie Brand-Miller, Ph.D., Thomas Wolever, MD, Ph.D., Kaye Foster-Powell, and Stephen Colagiuri, MD.

GL foods to limit (high numbers over 20)

Bagel 25
Corn Flakes 24
White Pasta 23
Raisins 28
Potato 26
White Rice 26
Risotto 36
Snickers Bar 23
Pancakes 39

 

GL foods (medium high numbers between 11-19)

Angel Food Cake 19
Banana 12
Dried Figs 16
English muffin 11
Sweet Potato 11
Brown Rice 16
Tortilla Chips 17
Yogurt 12

 

GL foods to have often (low numbers 10 or below)

Bran Cereal 4
Nuts 0
Apple 6
Oatmeal 9
Beans 8
Carrots 3
Grapes 8
Skim Milk 4