How many grams of sugar are there in a banana?

Depending on its size, one banana has about 14 grams of sugar. Large bananas can have up to 17 grams of sugar and about 68 calories. Despite their high sugar content, bananas have a low glycemic index, which means they have a low impact on blood sugar.

In addition to its sugar content, a banana contains an additional 13 grams of carbohydrates. These carbohydrates are comprised of fiber and starch. The fiber is not digestible, while the starch has to be converted to sugar to be digested. The rest of the banana is water, about 1 percent protein and less than 1 percent fat.