Previously in Part 1, we know that the glycemic index (GI) is important and cannot be ignored. For those who haven’t read Part 1, kindly click here to know more about GI before reading Part 2.
For your information, the same food will not have the same glycemic index (GI) score forever. There are many factors which can affect the GI score of food:
- The ripeness of fruits. For example, ripe fruit has a higher GI score than unripe fruit, because of higher sugar content.
- Protein, fat and/or acid contents of food. Gastric emptying and digestion rate will be slowed down if the protein, fat and/or acid contents are high, so the absorption of sugar into the bloodstream will then be slower as well, resulting in a lower GI score.
- Size of food particles. Food with a smaller size of food particles is easier to be absorbed and has a higher GI score than the same food with a bigger size of food particles.
- Cooking time of food. Longer cooking time will speed up starch gelatinization and its digestion rate, hence the food will have a higher GI score.
- Processing of food. Processed food has a higher GI score because it requires less digestion process and can increase the blood sugar levels in a faster way, compared to the same but unprocessed food.
- Types of carbohydrate in a food. The food with higher amylose (slowly digested) than amylopectin (rapidly digested) leads to lower GI score and vice versa.
- Fiber content of a food. The higher the fiber content, the slower the digestion rate, the slower the blood sugar level is raised, the lower the GI score.
- The sugar content of food. The higher the sugar content, the faster the blood sugar level is raised, the higher the GI score.
In conclusion, the glycemic index chart can be a very useful reference but it cannot be fully depended on due to the factors above. Actually, many people will then have a doubt, is following glycemic index the only way to control diet for diabetics? Stay tuned! We will discuss further in Part 3.