What does the glycemic index measure in nutrition?

The glycemic index is a measure that specifically assesses how quickly carbohydrate-containing foods raise blood glucose levels after consumption. Foods with a high glycemic index tend to cause rapid spikes in blood sugar, while those with a low glycemic index result in a slower, more gradual increase. This index can be particularly relevant for individuals managing blood sugar levels, such as those with diabetes or those seeking to control their weight.

The other options pertain to different nutritional aspects. Protein content focuses on amino acids needed for body function, fat content deals with lipid levels and their effect on health, and fiber is a critical component that promotes digestive health but does not correlate directly with how quickly food affects glucose levels. Each of these other components plays an important role in nutrition but does not relate to the specific function of the glycemic index.