What does the glycemic index measure?

The glycemic index (GI) is a ranking system that specifically measures how different carbohydrates affect blood sugar levels after consumption. It categorizes foods based on how quickly they raise blood glucose levels following eating. Foods with a high glycemic index cause a rapid increase in blood sugar, while those with a low glycemic index result in a slower, more gradual rise. This information is crucial, especially for individuals managing conditions like diabetes, as it helps them make informed dietary choices to maintain stable blood glucose levels.

In contrast, the other options incorrectly represent the purpose of the glycemic index, such as focusing on cholesterol levels, protein digestion, or caloric values. These aspects are important in nutrition but they are not the focus of the glycemic index.