Drawback of Glycemic Index?

Glycemic Index (GI) is a value assigned to food based on how it affects blood glucose levels. Nonetheless, GI value does not provide a complete nutritional picture. This is because considering the fat, protein, and fiber contents of a meal is important regardless of its GI. This emphasizes that calculate the GI of a meal separately may not always be the best measuring method of blood sugar levels. It’s important to consider the Glycemic Load (GL) of a food. GL is a value that combines both the quantity and quality of carbohydrates. It is the best way to compare blood glucose values of different types and amounts of foods. The formula to calculate the GL of a particular food or meal, 

Glycemic Load = GI x Carbohydrate (g) content per portion of ÷ 100.