How the Glycemic Index Works
Carbohydrates that break down slowly, releasing glucose gradually into the blood stream, have a low glycemic index. A lower glycemic index suggests slower rates of digestion and absorption of the sugars and starches in the foods and may also indicate greater extraction from the liver and periphery of the products of carbohydrate digestion. Examples of some low GI foods include:
The Glycemic Load: A Better Measure
The GI tells you how quickly a particular carbohydrate in food makes your blood sugar rise, but it doesn't take into account how many carbohydrates are found in a serving. The glycemic load, however, takes the number of carbs per serving into consideration along with the food's glycemic index. To find a food's glycemic load, you basically multiply its GI value by number of carbohydrates per serving. Therefore, the glycemic load allows us to compare the likely effect on blood sugar of realistic serving sizes of different foods.
What Influences the Glycemic Load/Index?
Many factors help determine your body's glycemic response to a particular food, including:
- Physical form, such as a whole apple vs. applesauce. Mashing foods tends to give them a higher glycemic index/load.
- Processing. The more processed or refined a food, generally, the higher its glycemic index/load will be.
- Ripeness. The riper the fruit, the higher its glycemic index.
- Acidity. The higher a food's acidity, the lower its glycemic index/load.
- Fiber. Particularly viscous fiber, a type of soluble fiber found in oats, barley, and other foods. Generally, the higher the fiber, the lower the glycemic index/load.
- Whether protein and fat were eaten with the food. The presence of high amounts of protein and fat will decrease the glycemic index/load.
The following foods, even in large amounts, when eaten alone are not likely to cause a significant rise in blood sugar because they contain little carbohydrate: meat, poultry, fish, avocados, salad vegetables, eggs, fish, and cheese.
Glycemic Load and Index Values for Common Foods
Here are glycemic index (GI) and glycemic load (GL) values for some common foods. I have included their fiber content as well. Keep in mind that GI/GL is just one tool. Other aspects of food, like vitamin, mineral, fiber, and phytochemical content, are also very important.
This table uses white bread as the reference for glycemic index. White bread has a glycemic index of 100 when used as the reference food.
Glycemic Load and Index Values for Common Foods
Here are glycemic index (GI) and glycemic load (GL) values for some common foods. I have included their fiber content as well. Keep in mind that GI/GL is just one tool. Other aspects of food, like vitamin, mineral, fiber, and phytochemical content, are also very important.
This table uses white bread as the reference for glycemic index. White bread has a glycemic index of 100 when used as the reference food.
| Food | GI | GL | *Fiber (g) |
| BEVERAGES | |||
| Milk, whole | 38 | 4 | 0 |
| Milk, skim | 46 | 6 | 0 |
| Chocolate milk (2%) | 49 | 12 | 1.2 |
| Coca-Cola | 90 | 22 | 0 |
| JUICES | |||
| Apple, unsweet | 57 | 17 | 0.3 |
| Carrot juice, fresh | 61 | 14 | 1 |
| Cranberry juice cocktail | 97 | 33 | 0.3 |
| Grapefruit, unsweet | 69 | 12 | 0.3 |
| Orange, unsweet | 71 | 18 | 0.5 |
| Pineapple, unsweet | 66 | 22 | 0.5 |
| Tomato, canned (no added sugar) | 54 | 6 | 1.1 |
| BREADS | |||
| Bagel, white (Lenders) | 103 | 35 | 1.8 |
| Baguette, plain | 136 | 21 | 1.8 |
| Oat-bran bread | 63 | 11 | 1.4 |
| Rye bread | 71 | 8 | 1.8 |
| White bread | 100 | 14 | 0.7 |
| 100% whole-grain bread | 73 | 10 | 4.5 |
| BREAKFAST CEREALS | |||
| All-Bran (Kellogg's) | 54 | 13 | 9.7 |
| Bran Chex | 83 | 15 | 4.9 |
| Cheerios | 106 | 21 | 2.6 |
| Corn Chex | 118 | 29 | 0.5 |
| Cornflakes | 130 | 33 | 0.8 |
| Corn Pops | 114 | 29 | 0.4 |
| Cream of Wheat | 105 | 30 | 3 |
| Crispix | 124 | 30 | 0.7 |
| Froot Loops | 99 | 25 | 0.6 |
| Golden Grahams | 102 | 25 | 0.9 |
| Grape-Nuts | 107 | 22 | 2.6 |
| Oat bran, raw | 78 | 4 | 1.5 |
| Raisin Bran | 87 | 17 | 4 |
| Rice Chex | 127 | 32 | 0.3 |
| Rice Krispies | 117 | 30 | 0.3 |
| Shredded Wheat | 107 | 21 | 3 |
| Special K | 98 | 19 | 0.9 |
| Total | 109 | 24 | 2.6 |
| GRAINS | |||
| Barley, pearl | 36 | 15 | 5.7 |
| Buckwheat | 78 | 22 | 6 |
| Bulgur (cracked wheat), boiled | 68 | 17 | 7 |
| Corn, sweet, cooked | 85 | 20 | 4 |
| Couscous, boiled 5 min. | 93 | 23 | 2.1 |
| Oats, (as porridge) | 83 | 18 | 4 |
| RICE | |||
| Long grain, white unconverted, boiled 15 min. | 71 | 29 | 0.6 |
| Uncle Ben's parboiled, 20 minutes | 107 | 39 | 0.6 |
| Basmati, white | 83 | 30 | 0.3 |
| Brown rice, steamed | 72 | 22 | 3 |
| DAIRY PRODUCTS, ETC. | |||
| Vanilla ice cream, light (1/2% fat) | 67 | 7 | 0 |
| Chocolate ice cream, premium (15% fat) | 53 | 6 | 0.5 |
| Milk, whole | 38 | 4 | 0 |
| Milk, skim | 46 | 6 | 0 |
| Vanilla pudding (instant, made w/ whole milk) | 57 | 8 | 0 |
| Fruit yogurt (low-fat) w/ sugar | 47 | 14 | 0 |
| Fruit yogurt (nonfat) w/ acesulfame K and Splenda | 33 | 6 | 1 |
| Soy milk, reduced-fat | 63 | 11 | 1 |
| FRUIT | |||
| Apple | 57 | 8 | 4 |
| Banana | 73 | 18 | 3 |
| Cherries | 32 | 4 | 2.8 |
| Dates, dried | 147 | 58 | 4.5 |
| Grapefruit, raw | 36 | 4 | 5 |
| Grapes | 66 | 11 | 1.2 |
| Kiwifruit | 68 | 7 | 4.1 |
| Orange | 69 | 7 | 3 |
| Peach | 40 | 62.4 | |
| Pear | 54 | 6 | 3 |
| Pineapple | 84 | 10 | 1.5 |
| Plum | 34 | 41.8 | |
| Prunes, pitted | 41 | 14 | 4.3 |
| Raisins | 91 | 28 | 3 |
| Cantaloupe | 93 | 6 | 1 |
| Strawberries | 57 | 1 | 2.8 |
| Watermelon | 103 | 6 | 0.6 |
| LEGUMES/BEANS | |||
| Black-eyed peas | 59 | 18 | 9.6 |
| Garbanzo beans | 39 | 11 | 6.6 |
| Kidney beans (canned) | 74 | 12 | 14 |
| Black beans, soaked overnight, cooked 45 min. | 28 | 7 | 13.1 |
| Lentils, red | 36 | 7 | 12 |
| Pinto beans (dried), boiled | 55 | 14 | 13 |
| Soybeans, green, boiled | 25 | 1 | 6.3 |
| PREPARED/CONVENIENCE FOODS | |||
| Chicken nuggets | 66 | 10 | 0.4 |
| Fish sticks | 54 | 10 | 0 |
| French fries, from frozen | 107 | 30 | 4.5 |
| Pizza, cheese, from frozen | 86 | 22 | 2 |
| Pizza, vegetarian (thin crust) | 70 | 17 | 3 |
| PASTA/NOODLES | |||
| Fettuccine, egg noodles | 57 | 25 | 2 |
| Macaroni, boiled 5 min. | 64 | 30 | 1 |
| Spaghetti, boiled 5 min. | 45 | 21 | 3.1 |
| Spaghetti, boiled 11 min. (durum wheat semolina) | 84 | 39 | 3.1 |
| SNACK FOODS | |||
| Corn chips | 60 | 15 | 1.8 |
| Fruit bars, strawberry | 129 | 32 | 0.5 |
| Popcorn, plain, cooked in microwave | 102 | 11 | 3 |
| Pretzels, oven-baked | 119 | 22 | 1 |
| SWEETS | |||
| Chocolate (milk) | 49 | 10 | 1.7 |
| Chocolate (white) | 63 | 18 | 0 |
| Roll-Ups (fruit leather w/added vitamin C) | 142 | 33 | 0 |
| Jelly beans | 112 | 30 | 0 |
| M&M's, peanut | 47 | 8 | 1 |
| Snickers bar | 97 | 32 | 1.5 |
| Twix cookie bar | 63 | 24 | 0.7 |
| NUTS | |||
| Cashews | 31 | 4 | 1.7 |
| Peanuts | 19 | 1 | 4 |
| SUGARS | |||
| Honey | 78 | 14 | 0 |
| Sucrose (sugar) | 97 | 10 | 0 |
| VEGETABLES | |||
| Broccoli, steamed | 0 | 0 | 2.5 |
| Kale, cooked | 0 | 0 | 2 |
| Spinach, raw | 0 | 0 | 2.2 |
| Zucchini, steamed | 0 | 0 | 1 |
| Lettuce, Romaine | 0 | 0 | 1 |
| Green peas | 68 | 4 | 4.4 |
| Sweet corn, boiled | 85 | 15 | 2 |
| Carrots, boiled and peeled | 70 | 3 | 3 |
| Potato, baked (russet) | 121 | 36 | 4 |
| Sweet potato, baked with skin | 69 | 22 | 6 |
So, What's the Bottom Line on Glycemic Load?
I always look for the bottom line. And in the case of glycemic load, it tends to lead you to less-processed types of carbohydrate-rich foods, like vegetables, fruits, whole grains, and beans/legumes.
The truth is, there is plenty of evidence that a mostly plant-based diet can reduce your risk of diseases like cancer, heart disease, and diabetes. And these foods tend to have lower glycemic index numbers.
But we have yet to determine whether a low-glycemic-index diet is really what helps prevent disease, or whether this effect comes mostly from eating a healthful variety of foods.