The Glycemic Index (GI) is a measurement of how fast carbohydrates in food are broken down into glucose and how long that takes to affect blood sugar levels. Low glycemic index carbohydrates are generally high in fiber and not overly processed. Glucose from low glycemic index carbohydrates is released at a slower rate, which means energy is used evenly over time, keeping the body from experiencing an insulin spike.
| Vegetable (per 100 grams cooked) | Glycemic Index Score | Carbohydrates in gram (portion size 100gr.) | G.I. Type |
| Artichoke | 15 | 2 | low |
| Asparagus | 14 | 1.5 | low |
| Beet | 63 | 8 | high |
| Bell Peppers | 10 | 2.5 | low |
| Broccoli | 10 | 1.5 | low |
| Brussels Sprouts | 16 | 4 | low |
| Cabbage | 10 | 2.3 | low |
| Carrot | 70 | 7 | high |
| Cauliflower | 15 | 2.5 | low |
| Celery | 15 | 1 | low |
| Green Beans | 14 | 3.5 | low |
| Lettuce (average) | 10 | 1.7 | low |
| Mushroom | 10 | 0.5 | low |
| Onion | 10 | 4 | low |
| Parsnips | 98 | 11 | low |
| Potato, boiled | 56 | 16.5 | medium |
| Potato, chips | 75 | 37 | high |
| Potato, mashed | 70 | 16 | medium |
| Potato, sweet | 50 | 20 | low-medium |
| Swede | 71 | 1 | high |
| Sweet Corn | 55 | 19 | medium |
| Yam | 50 | 32 | low-med |
Food that is 55 or less are considered to be at a low glycemic index level. At 56 to 69, food is of a medium glycemic index level and 70 or more is high. Some foods are designated with a range of GI levels, from low to medium to high, depending on ripeness and size (the riper and the larger, the higher the GI). Adding fiber, fat and protein to a meal can help slow down the absorption rate of glucose from carbohydrates. The rule of thumb is to consume carbohydrates from fruits, vegetables, whole grains and legumes for a low glycemic load. Eating low glycemic index foods may help with concentration and steady energy levels as well as produce a feeling of fullness, helping to avoid overeating.
In contrast, high glycemic index carbohydrates are generally processed foods such as white bread, pasta and rice, baked products, crackers, low-fiber cereals, raisins, sugary beverages and candy. Just as low GI foods provide long-lasting energy, high GI foods provide quick bursts of energy. When blood glucose and insulin move up and down quickly or stay high, it is disruptive to the natural blood glucose balance, which may result in insulin resistance. Health problems associated with insulin resistance include Type 2 diabetes, obesity, high blood pressure, stroke and heart disease.
Glycemic Index for Fruits
| Fruit | Glycemic Index Score | Carbohydrates in gram (portion size 100gr.) | G.I. Type |
| Apple | 39 | 12 | low |
| Apple Juice | 40 | 10 | low |
| Apricot | 57 | 7.5 | medium |
| Banana | 54 | 23 | low-medium |
| Cantaloupe Melon | 65 | 3 | medium-high |
| Cherries | 22 | 10 | low |
| Fruit drink from concentrate | 66 | - | high |
| Grapefruit | 23 | 6 | low |
| Grapefruit Juice | 48 | 8 | medium |
| Grapes | 46 | 15 | low-medium |
| Kiwi | 52 | 9 | medium |
| Mango | 56 | 14.5 | medium |
| Orange | 44 | 6 | medium |
| Orange Juice | 47 | 9 | medium |
| Peach | 42 | 7 | medium |
| Pear | 37 | 10 | low |
| Pineapple | 66 | 10 | medium-high |
| Pineapple Juice | 46 | 10 | medium |
| Plum | 38 | 9 | low |
| Raisins | 64 | 70 | medium-high |
| Strawberry | 40 | 6 | low |
| Sultanas | 56 | 66 | medium |
| Watermelon | 72 | 7 | high |
Whole foods with more nutrients and fiber tend to be lower on the glycemic index. If a cereal or bread has 3g of fiber or more per serving, it is considered to be on the lower side of the glycemic index. Avoid baked goods and cereals that have less than 3g of fiber.