The glycemic index (GI) measures the speed at which sugars, or carbohydrates, contained in food are absorbed. A high glycemic index means that ingesting the food causes a spike in blood sugar immediately after consuming it, and conversely, a low glycemic index implies a slow and gradual absorption of carbohydrates. Studies now show that a healthy diet should be a low GI diet . Here are the main explanations:
In the short term: it helps stabilize our energy levels
The level of glucose (or sugar) in the blood must always remain constant. When we raise it excessively with the ingestion of high GI foods, the body will react by secreting a lot of insulin, a hormone that brings excess sugar into our cells so that they produce energy , and which therefore causes it to drop suddenly in the blood. What follows is “reactive hypoglycemia”, the famous feeling of energy after a meal: strong feeling of fatigue, loss of energy, lack of concentration , stress and anxiety , and... craving for something sweet. Sugar calls for sugar so watch out for the vicious circle!
In the medium term: it limits weight gain
If this energy generated by the intake of carbohydrates is not used immediately, the body will secrete a hormone, insulin, which will store the excess sugar for future needs, first in the liver, then muscles (provided you have enough muscle mass!) and finally, in the form of fats. As you will have understood, too much and too regular consumption of high GI foods promotes weight gain.
In the long term: it reduces the risks of diabetes and cardiovascular diseases
Regular and repeated ingestion of high GI foods forces our pancreas to massively produce insulin. Little by little, it risks becoming exhausted, thus leading to the development of pathologies such as type 2 diabetes, and to an increase in cardiovascular risks and chronic inflammatory diseases.
In practice :
Avoid ultra-processed products containing too many hidden fast sugars, eat whole grains and flours and make sure you always have a supply of fiber, quality proteins and good fats on your plate. They all slow down the speed of sugar absorption, and therefore lower the GI of your meal.
Sources: The new IG Diet, Angélique Houlbert and Elvire Nérin