Glycaemic loadGlycemic load · GL

Glycaemic load multiplies a food's glycaemic index by the grams of carbohydrate in a typical serving, then divides by 100. It answers the practical question the index alone cannot: how much will this portion actually move my blood glucose?

It matters because glycaemic index is measured against a fixed 50-gram carbohydrate dose, which distorts foods that are mostly water or fibre. Watermelon has a high index but very little carbohydrate per slice, so its load is low; the index makes it look like a problem it is not.

In practice load is the more useful of the two numbers, and both matter more for people managing diabetes or insulin resistance than for a healthy person eating mixed meals — protein, fat and fibre eaten alongside carbohydrate blunt the response considerably.