Glycemic Index Limits
The glycemic index of a food is a difficult parameter to establish, as it is influenced by many factors, we see the main ones:
- technological manipulation of food: the more an industrial product is processed and the greater its glycemic index.
For example, the various pasta shapes have different glycemic indexes.
- Cooking mode and degree: the glycemic index of the food increases with time and cooking temperature; for this reason it is greater in heated foods than in fresh ones.
- Variety and degree of ripeness: the glycemic index of fruit and vegetables increases with the maturation of the vegetable; this parameter is also influenced by the geographical area of production and the respective characteristics of the climate and the cultivation soil.
- Amount of fats, proteins and fiber present in the food: by increasing digestion times, these food substances negatively modulate the insulin response.
Furthermore, it should be borne in mind that the glycemic index is, in certain aspects, a misleading parameter, in fact:
despite having the same glycemic index, apricots are not like spaghetti!
This somewhat provocative phrase serves to introduce an extremely important concept. In fact, although the glycemic index is the same, to increase the blood sugar level by a similar value it is necessary to introduce a quantity of apricots seven times higher than that of spaghetti. In fact, in apricots, the percentage of carbohydrates is particularly low, especially when compared to that contained in pasta.
30 grams of pasta (IG = 60) determine a higher insulin release compared to 10 grams of glucose (IG = 100).
Therefore, basing one's food choices on the glycemic index alone makes no sense.
What is Glycemic Load
For this reason it is very important to consider a parameter, called glycemic load (CG), which also takes into account the quantity of carbohydrates present in the food. This criterion is expressed by the following formula:
GLYCEMIC LOAD = (Glycemic Index xg carbohydrates) / 100
Between the glycemic index and the glycemic load there is a relationship analogous to that between the specific weight and the weight of a material.
Let's look at an example: the specific weight of iron is without a shadow of doubt higher than that of cotto. Despite this, the impact on the foot of a brick fallen from above is less painful than that caused by a bolt that hits the foot falling from the same height.
Even if there are limits, the evaluation of the index and glycemic load of food can be useful in various cases:
a diabetic, in fact, must favor low GI foods, in order to avoid excessive increases in blood glucose concentration. However, in order for the desired effect to occur, it is also important to contain the overall glycemic load of the meal.
After physical exercise, high and medium glycemic index foods are preferable, since this promotes insulin secretion. In such situations this hormone has particularly important functions, since it promotes recovery, restoring glycogen stores and favoring the entry of various nutrients (glucose, amino acids and fatty acids) into the cells.