Anyone who studies diets will soon come across the concept of the glycemic index. The glycemic index indicates how quickly carbohydrates are converted into glucose. In other words: how quickly they are absorbed into the blood. For those who want to maintain their weight, it is important to eat products that score low on the glycemic index list. This keeps blood sugar levels and insulin production under control and reduces binge eating. The glycemic index, abbreviated GI, was developed as a nutritional tool for the prevention of obesity, diabetes and heart disease. It helps to choose foods that can prevent food cravings.
Contents
- Glycemic index
- Meaning of glycemic index list
- Fast and slow sugars
- High glycemic index with grape sugar
- Glucose+insulin
- Insulin for transport of glucose to the cells
- Keep blood sugar levels under control
- The glycemic load
- Is it wise to adjust your diet to the glycemic index?
Glycemic index
You’ve probably heard about the term glycemic index, but you still don’t know what exactly it is and what it’s good for. To put it briefly: the glycemic index indicates how quickly carbohydrates are converted into glucose. Let me explain this.
The body uses 3 nutrients as an energy source:
- carbohydrates;
- proteins (also called proteins);
- fats.
Meaning of glycemic index list
The body can use proteins and fats directly as fuel, but carbohydrates must first be converted into glucose (better known as blood sugar). You can read how quickly the carbohydrates are converted into glucose from the glycemic index list:
- the higher a food product scores in the list table, the faster it is converted into glucose;
- a product that scores low needs more time to be processed as fuel.
Fast and slow sugars
An athlete will eat dextrose during exercise, because it is absorbed very quickly by the blood and therefore gives almost immediate results. If he were to eat a whole wheat sandwich instead of dextrose, it would take much longer before the extra energy was available. This is of course because (grape) sugar scores very high on the glycemic index, while whole wheat bread has a relatively low score. Nowadays you hear a lot about slow sugars. This means that these products are slowly converted into glucose.
High glycemic index with grape sugar
The Glycemic Index (GI) was introduced in the early 1980s to determine the speed at which carbohydrates (sugars) are converted into glucose. The index therefore provides insight into the speed at which the various carbohydrates are absorbed. Glucose (grape sugar) sets the standard at 100%. To give you an impression, below is a small table.
| Glycemic index | |
| 100% | glucose (grape sugar) |
| 80-90% | mashed potatoes |
| honey | |
| corn flakes, raisins, brown rice | |
| 70-79% | Whole grain bread |
| White rice | |
| potatoes | |
| corn | |
| 60-69% | White bread |
| banana |
Glucose+insulin
Why is it so important that foods are converted slowly into glucose? Well: carbohydrates are converted into glucose. This glucose must then be transported to the cells, where it is used as an energy source. The transport of glucose to the body cells is done by another substance called insulin .
Insulin for transport of glucose to the cells
Insulin is vital for the fuel supply of our cells. When you eat a product that scores high on the glycemic index, it is quickly converted into glucose. The blood sugar level in the blood rises rapidly. An enormous amount of glucose must be transported to the cells in a very short time. The body is therefore obliged to produce a large amount of insulin, but cannot estimate the precise amount. Therefore, it produces a huge amount of insulin.
Some of this insulin is used for transport, but the excess insulin is stored in the body as fat. The insulin performs its job perfectly: the glucose is transported to the body cells at a rapid pace. This causes the blood sugar level to drop incredibly quickly. The result of this is an uncontrollable sugar level. This leads to:
- fatigue;
- concentration problems;
- headache;
- and a weak feeling.
Keep blood sugar levels under control
It is therefore very important to eat products that score low on the glycemic index. This keeps blood sugar levels and insulin production under control and you will experience fewer bouts of binge eating. After all, these are the result of a rapidly falling sugar level: you feel weak and hungry and quickly take a piece of chocolate because this will quickly cheer you up.
Chocolate , for example, scores high on the glycemic index and is therefore quickly converted into glucose. Your blood sugar level skyrockets. The body produces a large amount of insulin, transports the glucose to the cells and your sugar level plummets back down. You feel weak and crave a piece of chocolate.
A Swedish study conducted over many years has recently also shown positive health effects of chocolate. Consuming small portions of good quality chocolate occasionally is said to reduce heart problems.
The glycemic load
The amount of carbohydrates in a food does not count in the glycemic index. That can produce strange values. Watermelon, for example, has a high glycemic value of 72. This has to do with the quantity. The glycemic index always refers to 50 grams of carbohydrates in a food. But you have to eat a lot of watermelon to get these 50 grams of carbohydrates. Namely more than 800 grams. This is quite unrealistic for daily nutrition. A normal portion of watermelon does not increase blood sugar levels as much as the glycemic index suggests. For this reason, the glycemic load (GL) has been added to the table. In addition to the quality of the carbohydrates, the glycemic load also takes into account the amount consumed. Because it also influences the increase in blood sugar levels.
To illustrate, the glycemic load of a serving of watermelon is only 6, while white rice comes in at 28 .
Is it wise to adjust your diet to the glycemic index?
It is not wise to tailor your diet solely to the glycemic index. The figures are not always accurate and it is difficult to apply in the daily diet. There is also the risk of a one-sided diet with too many proteins and fats. However, the glycemic index can serve as a guideline towards a balanced diet. The concept provides important information about the quality of carbohydrate-containing foods.