The glycemic index (GI) is a value given to foods based on the speed with which glucose (sugar) levels rise in the blood after eating them.
The GI is mainly taken into account when drawing up diet plans to help with glycemic control. In practice, it is often used by people with diabetes or, on the other hand, in weight management.
Which foods have a high or low GI? In general, how can you evaluate them?
Foods with a low GI take longer to digest and therefore increase the feeling of satiety. This is the case with beans: as they are a very firm food, they need to be chewed, digested and metabolized by the body, a process that takes some time. In addition, the fact that it is rich in fiber slows down the absorption of glucose. In other words, the speed with which it turns into sugar and is absorbed by the body is slower and it has a low glycemic index.
On the other hand, orange juice is a food considered to have a high glycemic index because, as well as being liquid, which facilitates the speed with which it is absorbed by the body, it has a high concentration of fructose and carbohydrates, which turn into sugar in the blood.
Based on the GI values, foods are classified into three categories:
- Low GI: when the GI is less than or equal to 55;
- Medium GI: when the GI is between 56 and 69;
- High GI: when the GI is greater than or equal to 70.
A good strategy for avoiding foods with a high GI is to eat them as naturally as possible, opting to eat the peel of fruit and vegetables whenever possible. Even so, there are some tips for assessing whether a food has a high or low GI: the more cooked or processed a food is, the higher the GI; the riper a fruit or vegetable is, the higher the GI, and peeled fruits and vegetables have a lower GI than peeled ones.
Controlling the glycemic index should also be taken into account to improve physical training and, consequently, help with weight management.
Before training, athletes should opt for low to moderate GI foods, such as bananas and sweet potatoes, as they will raise blood glucose slowly. If the workout is intense and lasts more than an hour, you should eat high-GI foods. After exercise, athletes should prefer to eat foods with a medium to high GI to replenish carbohydrate levels and speed up muscle recovery.
What is the difference between GI and glycemic load?
The glycemic index is a factor used to compare carbohydrates in terms of their ability to increase blood glucose levels, and is a qualitative index. The glycemic load (GC) relates the quality of the carbohydrate in the food - whether it is quickly or slowly absorbed - and the amount consumed. In other words, the more carbohydrate, the greater the change in blood glucose.
For example, watermelon has a high GI (80). As it is a fruit that has little carbohydrate per portion, the GC is low (5). For there to be a significant increase in blood glucose, it was necessary to consume several portions.
The glycemic load is classified as follows:
- Low CG: values up to 10;
- CG average: values from 11 to 19;
- High CG: prices from 20.
By controlling blood sugar, eating low-GI foods, increasing the interval between meals and practicing intermittent fasting, always accompanied by a professional, you can regain your metabolic balance and manage your weight.
