The Glycemic index was discovered and designed by a nutrition professor out of the University of Toronto. He took subjects into the lab in order to see how high certain carbohydrates raised blood sugar. This was a turning point in how diabetics could eat.
Carbohydrates were once thought to be “all bad” to diabetics and nutrition took a hit as they missed out on certain vitamins, minerals, and antioxidants. It turns out, not all carbs are “all bad” and there are actually good carbs, somewhat good carbs, and bad carbs. This was discovered by giving the subject certain carbs and checking their blood sugar levels after a certain amount of time. One amazing fact is that it was found fattier or higher fiber carbs spiked blood sugar less, than what were thought to be “low-carbohydrate” foods. The subjects actually had lower blood sugar after a bowl of chocolate ice cream, than after eating a slice of bread.
How Glycemic Index Works
What they found in the lab is that table sugar or pure glucose was the highest number out of all the foods. They gave that a 100 on the index. Then, they compared many other carbohydrate foods to how high they raised the blood sugar.
They gave the subjects a variety of other foods one at a time, then checked the blood sugar within a specified time frame. Carbohydrates without adequate fiber or protein tended to “spike” blood sugars and others that were higher in protein and fiber burned more slowly in the body. On the glycemic index, the higher the number on the scale, the more the blood sugar tends to spike after eating it. The lower the number, the less the blood sugar tends to rise.
According to these numbers, three groups were assigned. Foods with- low-glycemic, moderate-glycemic, or high-glycemic. Diabetics can enjoy foods from any of these groups, just by practicing portion control. If the food is low on the index, you can have bigger portions. If it is high, eat less of that food. Here is an example of the groups:
- Low Glycemic Foods – 55 or lower (larger portions okay)
- Moderate Glycemic Foods – 56 to 69 (eat less of these)
- High Glycemic Foods – 70 or higher (eat sparingly)
Now, here are some of the foods and how they measure up on the glycemic index. They are organized by group and serving size to get you started. It is always best to try and eat below 70 if possible, and if you want to indulge just be sensible about it.
Low Glycemic Foods (55 or lower) | Glycemic Number |
Fruits (1 cup or 1 Medium) | |
Apples | 40 |
Apricots | 31 |
Cherries | 22 |
Grapefruit | 25 |
Strawberries | 40 |
Orange | 42 |
Beans and Legumes (1 Cup) | |
Butter Beans | 31 |
Kidney Beans | 28 |
Lentils | 26 |
Peanuts | 13 |
Peas | 22 |
Soy Beans | 15 |
Split Peas | 32 |
Vegetables (1 Cup) | |
Asparagus | 8 |
Broccoli | 6 |
Cabbage | 6 |
Carrots | 47 |
Corn | 54 |
Spinach | 6 |
Tomatoes | 6 |
Cereal (1 Cup) | |
Bran | 50 |
Oatmeal, Regular | 55 |
Drinks (8 oz.) | |
Apple Juice | 39 |
Carrot Juice | 43 |
Orange Juice | 46 |
Tomato Juice | 23 |
Lemonade | 54 |
Breads and Grains (1 Cup or 1 Slice) | |
Rye Bread | 50 |
Pearl Barley | 25 |
Quinoa | 53 |
Uncle Ben’s Instant White Rice | 38 |
Corn Tortilla | 52 |
Wheat Tortilla | 30 |
Whole Grain Spaghetti | 42 |
Snacks and Miscellaneous | |
Low-Fat Yogurt | 33 |
Corn Chips | 42 |
M & M’s (Peanut) | 33 |
Popcorn | 55 |
Hummus | 6 |
Banana Cake | 47 |
Moderate Glycemic Foods (56 to 69) | |
Fruits (½ Cup or 1 Medium) | |
Grapes | 59 |
Watermelon | 72 |
Raisins | 64 |
Dried Dates | 103 |
Vegetables (½ Cup) | |
Sweet Potato | 61 |
Beets | 64 |
Cereal (¾ Cup) | |
Fruit and Fiber | 61 |
Muesli | 56 |
Drinks (8 oz.) | |
Cranberry Juice | 56 |
Fruit Punch | 67 |
Pepsi | 58 |
Breads and Grains (½ Cup or 1 Slice) | |
Bagel, Whole Grain | 69 |
Baguette, Whole grain (Small, thin) | 57 |
Oat Bread | 65 |
Hamburger Bun | 61 |
Whole Wheat Bread | 69 |
Pita Bread | 68 |
Snacks and Miscellaneous | |
Shortbread | 64 |
Ice Cream | 62 |
Macaroni and Cheese | 64 |
Potato Chips | 56 |
High Glycemic Foods (70 or higher) | |
Fruits (¼ Cup or 1 Small) | |
Dried Dates | 103 |
Watermelon | 72 |
Vegetables (¼ Cup) | |
Baked Potato, Russet | 85 |
Broad Beans | 79 |
French Fries | 75 |
Mashed Potatoes | 85 |
Parsnips | 97 |
Pumpkin | 75 |
Red Potatoes, Boiled | 89 |
Cereal (½ Cup) | |
Coco Puffs | 80 |
Corn Flakes | 77 |
Fruity Pebbles | 113 |
Grape Nuts | 75 |
Oatmeal, Instant | 79 |
Drinks (8 oz.) | |
Rice Milk | 92 |
Gatorade, Regular Full Sugar | 89 |
Breads and Grains (¼ Cup or 1 Slice) | |
Gluten Free Bread, Multigrain | 79 |
Rice Bread | 72 |
Baguette, White (Large) | 95 |
Bagel, White | 72 |
White Bread | 75 |
Kaiser Roll | 73 |
White Rice | 73 |
Snacks and Miscellaneous | |
Waffles, White Flour | 76 |
Graham Crackers | 74 |
Rice Cakes | 82 |
Soda Crackers | 74 |
Fruit Rolls | 99 |
Pretzels | 83 |
Tips For Success
The glycemic index can help you manage your blood sugars and maintain a healthy diet packed with nutrients. You just need to use it carefully. Here are some tips to help you be successful:
- The “Glycemic Load” of foods is lowered by including proteins and fiber with your carbs. Some carbs contain them, and if not eat something on the side. Try peanut butter or cheese with crackers to help “slow the burn.”
- The higher on the scale, the smaller portion you can eat.
- The longer your fruits and vegetables ripen, the more the fiber breaks down. This makes the GI number rise. Try to eat fruits and vegetables fresh and crisp.
- The more you cook or process a low or moderate GI food, the higher the number gets. For example, baked or even mashed russet potatoes can be high on the scale. Learn to eat things like, baked sweet potatoes, al dente pasta, or mashed cauliflower.
- You can “mix and match” your GI foods. Eat a small portion of a high GI food and a larger portion of a low GI food in the same meal.
- Try not to avoid foods that have important nutrients if they are high on the GI index. You will miss out on things your body needs. For instance, oatmeal may have a higher number, but is an excellent grain source. Oatmeal is bulky and digests more slowly. Just stick to a reasonable portion size.
The glycemic index can be pretty easy to use, and your whole family can enjoy the same meals you make. No special diet, no cooking special meals, and buy whatever you normally buy at the store!
Source: American Diabetes Association.