Final answer:
The glycemic index ranks carbohydrates based on how quickly they raise blood sugar levels. Carbohydrates with a high glycemic index cause a rapid increase in blood sugar levels, while carbohydrates with a low glycemic index cause a slower and more gradual increase.
Step-by-step explanation:
Carbohydrates, which include sugars, starches, and fiber, are used by the body for energy. The glycemic index (GI) is a scale that ranks carbohydrates based on how quickly they raise blood sugar levels. Carbohydrates with a high glycemic index, such as white bread and sugary snacks, cause a rapid increase in blood sugar levels, while carbohydrates with a low glycemic index, such as whole grains and vegetables, cause a slower and more gradual increase.