Why glycaemic impact matters beyond GI
Glycaemic index (GI) is measured under controlled conditions for individual foods consumed in isolation. Real meals are mixtures of foods with different macronutrient profiles, and the combined glycaemic response is substantially influenced by fat and protein content, cooking method, and food structure. A high-GI food in isolation may have a moderate glycaemic impact when combined with fat, protein, and fibre in a mixed meal.
Glycaemic load (GL), which multiplies GI by the carbohydrate amount, gives a better meal-level estimate than GI alone but still ignores fat, protein, and fibre blunting. This tool incorporates all four macronutrients and food type context for a more holistic estimate.