Low glycemic fruit charts provide information about how fruits affect blood sugar and insulin, states Harvard Medical School. The lower a fruit falls on the glycemic chart, the less it affects blood sugar and insulin levels.
Glycemic charts can help determine which foods are healthiest to keep blood sugar stable, according to About.com. The rating on the glycemic index, or GI, shows how much a food raises blood glucose, and the glycemic load, or GL, indicates a food's impact on blood sugar with a specific portion size. Knowing how a fruit scores on the GI can aid in meal planning. The healthiest fruits are those with the lowest scores on the GI and have the lowest GL, meaning they do not cause extreme spikes in blood sugar.
Grapefruit has a GL of 3, the lowest of all common fruits, according to Harvard Medical School. Oranges, pears and watermelon each have a GL of 4. Peaches, fresh or canned, and canned pears each have a GL of 5. Apples are also a healthy choice with a GL of 6. Sweeter fruits include prunes, with a GL of 10; grapes, with a GL of 11; and bananas, with a GL of 16. Raisins are the sweetest of all common fruits, with a GL of 28.