For example, carrots have a high GI of 47, but you have to eat a pound and a half of them for there to be a steep rise in blood sugar.
carrots are full of water, not to mention roughage, so they don't have high caloric density per unit mass/weight
the glycemic load is precisely articulating the index number adjusted per unit mass to account for stuff like caroots or beets etc.
So basically if you ate de-hydrated fruit or vegetables that will load higher (per unit mass) than stuff full of water...because whater has no cals...so water and starch dilute glycemic index
The glycemic load is calculated by multiplying the glycemic index of a food by the amount of carbs in a 10 gram portion of the food.
In practice, you can dilute glycemic index using fat and protein in addition to water.