Sort of. The glycemic index is not really useful because it is based on arbitrary quantities of food. Glycemic load was created to be useful to people, as it is based on reasonable quantities people would eat. Like GI says watermelon is bad because its calories come from sugar. But it is based on eating 100g of carbs from watermelon. That's a huge amount of watermelon, which is mostly water. GL shows watermelon is fine, because you only eat 10g of carbs from it in a normal serving.

So glycemic load is more or less glycemic index times carbohydrate density times the quantity of food you'd need to eat before feeling full?

Thanks. I never realized that glycemic index and load were different things.

Yes. https://en.wikipedia.org/wiki/Glycemic_index:

"The GI represents the total rise in a person's blood sugar level following consumption of the food; it may or may not represent the rapidity of the rise in blood sugar. The steepness of the rise can be influenced by a number of other factors, such as the quantity of fat eaten with the food."

But only "related to". GI is complicated. The whole blood sugar thing is complicated. I don't just mean in principle, I mean in practice, too. Measuring your own body's own reactions to foods may be the most practical route to go; reading that page leads one to the conclusion that any concrete numbers for GI you ever see are at best weak approximations even under the best of circumstances.

Which is a pity, seeing as how it seems like it would be very useful.