Glycaemic Index (GI)

A ranking system for carbohydrate-containing foods based on the speed and extent to which they raise blood glucose levels after consumption, relative to pure glucose (GI = 100) or white bread (GI = 100 on some scales). Fructose has a low GI (~15–25) due to its liver-first metabolism, while maltodextrin has a high GI (~85–110). The GI of an ingredient in isolation does not always predict the GI of the finished food product, which depends on portion size, cooking method, fat/protein/fibre content, and other factors.