Description
Function
Benefits
Precautions
Risks
Research and general acceptance
Questions to ask your doctor
Resources
What are the Glycemic index diets?
Glycemic index diets rank carbohydrates based on their ability to affect blood glucose (sugar) levels. These diets generally consider foods high in carbohydrates, such as bread, sugar, and pasta, as bad and low carbohydrate foods, such as meat, fish, and dairy products, as good.
What are the Origins of the Glycemic index diets?
Low-glycemic diets concepts were first developed in the 1960s and were originally designed for individuals with diabetes. At that time, the prevailing medical attitude was that a diet emphasizing well-balanced foods while paying special attention to carbohydrates (carbs) and avoiding carbohydrate-rich foods, helped to control blood sugar and insulin levels. This came after a number of medical studies linked eating foods high in carbohydrates with elevated blood glucose levels in diabetics. In the 1980s, researchers developed the glycemic index (GI).
Before 1981, carbohydrates were classified as simple or complex. Simple carbohydrates included fructose (fruit sugar), sucrose (table sugar), and lactose (milk sugar). Complex carbohydrates are also composed of sugars but the sugar molecules are strung together to form longer and more complex chains. Foods high in complex carbohydrates include vegetables, whole grains, and beans. In 1981, researchers David Jenkins and Thomas Wolever of the University of Toronto Department of Nutritional Sciences developed the glycemic index (GI) and published a study suggesting that using the glycemic index of foods was a more accurate way of classifying carbohydrates than the simple and complex system.
Since 1981, dozens of low-carb diets and diet books have come out, using the glycemic index as the primary guiding principle. Among the more popular glycemic index-inspired diets are the Sugar Busters Diet, Zone Diet, Protein Power Diet, Suzanne Somers diet, and South Beach Diet. In general, these diets are similar. Their differences are in the zeal that they limit carbohydrate intake.
In 1997, epidemiologist and nutritionist Walter Willett of the Harvard School of Public Health developed the glycemic load as a more accurate way ofrating carbohydrates compared to the glycemic index. This is because the glycemic load factors in the amount of a food eaten which the glycemic index does not. The glycemic load of a particular food is determined by
multiplying the amount of net carbohydrates in a serving by the glycemic index and dividing that number by 100. Net carbohydrates are determined by taking the amount of total carbohydrates and subtracting the amount of dietary fiber. For example, popcorn has a glycemic index of 72, which is considered high, but a serving of two cups has 10 net carbs for a glycemic load of seven, which is considered low.
Glycemic index of common foods
| Food item | GI (Glucose = 100) | GI (Bread = 100) | Serving size (grams or milliliters) |
| Beverages | |||
| Coca Cola, soft drink (Atlanta, GA, USA) | 63 | 90 | 250 ml |
| Apple juice, unsweetened | 40 | 57 | 250 ml |
| Orange juice (mean of Canada, Australia, & USA) | 52 | 74 | 250 ml |
| Breads | |||
| Bagel, white, frozen (Lender’s Bakery, Montreal Canada) | 72 | 103 | 70g |
| Wonder, enriched white bread | 73 | 105 | 30 g |
| Healthy Choice Hearty 7 Grain Wheat bread (Con Agrag Inc., USA) | 55 | 79 | 30 |
| Dairy products and alternatives | |||
| Ice cream, regular flavor, not specified (mean of Canada, Italy, & USA) | 61 | 87 | 50g |
| Milk, full-fat (mean of Italy, Sweden, USA, Australia, and Canada) | 27 | 38 | 250g |
| Milk, skim (Canada) | 32 | 46 | 250 g |
| Fruit and fruit products | |||
| Apples, raw (mean of Denmark, New Zealand, Canada, USA, and Italy) | 38 | 52 | 120g |
| Banana, raw (mean of Canada, USA, Italy, Denmark, and South Africa) | 52 | 74 | 120g |
| Grapefruit, raw (Canada) | 25 | 36 | 120g |
| Pasta and noodles | |||
| Macaroni and cheese, boxed (Kraft General Foods Canada, Inc., Don Mills, Canada) | 64 | 92 | 180g |
| Spaghetti, white or type not specified, boiled 10–15 min (mean of Italy, Sweden, and Canada) | 44 | 64 | 180g |
| Ravioli, durum wheat flour, meat-filled, boiled (Australia) | 39 | 56 | 180g |
| Vegetables | |||
| Green peas, frozen, boiled (mean of Canada and India) | 48 | 68 | 80g |
| Carrots, not specified (Canada) | 92 | 131 | 80g |
| Baked potato, without fat (mean of Canada and USA) | 85 | 121 | 150g |
The Gale Encyclopedia of Diets © 2008 The Gale Group, Inc. All rights reserved.
