Tracy Norris
The glycemic index and glycemic load are values that show the influence of foods on blood sugar levels. Here you can find out how the values are interpreted and what you should pay attention to.
Glycemic index and glycemic load for better blood sugar levels
The glycemic index and the glycemic load reflect the influence of food on the blood sugar level and thus also on the insulin level. The glycemic index and glycemic load were developed to help people with diabetes make food choices. They are now used by many people who want to eat consciously. Even their own forms of nutrition have emerged from this, e.g. B. the Glyx diet or the Logi method.
The following applies: the higher the glycemic index and the higher the glycemic load, the greater the influence on the blood sugar level and the less well the food fits into a healthy diet. But it’s not that simple.
Which glycemic values are good, and which are bad?
The glycemic index and glycemic load values are interpreted as follows:
Glycemic Index (GI):
- Low GI: 55 and below
- Average GI: Scores between 56 and 69
- High GI: 70 and above
Glycemic Load (GL):
- Low GL: 10 and below
- Medium GL: Values between 11 and 19
- High GL: 20 and above
So if you want to strain your blood sugar level as little as possible, you should choose foods with low values, although it is better to use the values of the glycemic load.
Of course, you can also eat foods with a medium GL or even high GL, just be careful not to eat too much of them or combine them with foods with a low GL. Because you usually don’t eat just one food, but a dish with different foods, this ultimately has a completely different GL than the individual foods and can therefore also have a completely different influence on the blood sugar level.
Better use the glycemic load
The problem with the glycemic index is that it doesn’t take into account the carbohydrate content in foods. It always refers to 50 g of carbohydrates, no matter how high the carbohydrate content of the food in question may be per 100 g. The glycemic load, on the other hand, refers to 100 g of the entire food, which of course makes much more sense.
It is therefore possible that food has a high glycemic index and at the same time a low glycemic load – namely when the food contains only a few carbohydrates per 100 g.
The following example shows the difference:
- A peach has a GI of 76. However, since it only has a low carbohydrate content of 9 g per 100 g, the influence on blood sugar levels is small. Therefore, the glycemic load is only 6.8: calculation GL = 76 x (9 g / 100 g) = 6.8
- White bread has a GI of 73. However, about half of white bread is carbohydrates (50g per 100g), so – despite the lower GI – it has a much higher impact on blood sugar levels than a peach. The glycemic load shows this clearly and is 36.5: Calculation GL = 73 x (50 g / 100 g) = 36.5
How foods affect blood sugar levels
If you are new to glucose metabolism, this section will provide you with the details so you can understand why the glycemic index and glycemic load are so interesting for a healthy diet.
This is how sugar is digested
During digestion, glucose from food is absorbed into the blood from the small intestine. The blood sugar level rises. This response is called the glycemic response. From the blood, the glucose is then distributed to the cells, since they need the glucose for their energy supply.
Glucose transport is controlled, among other things, by the hormone insulin, which is produced in the pancreas. As soon as the blood sugar level rises, the pancreas releases more insulin. The insulin level rises. As soon as the glucose is distributed from the blood into the cells, the blood sugar level begins to fall again. The body then signals hunger again and the cycle begins again.
The influence on the blood sugar level is so different
This is where the glycemic index and glycemic load come into play: If you eat a piece of white bread, for example, the blood sugar level quickly rises very high and the pancreas produces copious amounts of insulin to lower the blood sugar level again because a permanently high blood sugar level is harmful and should be therefore be avoided.
On the other hand, if you eat a peach, the blood sugar level does not rise as high, which means that the pancreas has to produce less insulin, the blood sugar level falls more slowly and the feeling of satiety lasts longer. So the peach has a low glycemic load, while white bread has a high one.
With a high glycemic load, the risk of diabetes increases
It is known that a high-sugar diet can increase the risk of diabetes. But there are foods that increase the risk of diabetes even though they don’t appear to contain any sugar, such as B. the mentioned white bread.
With the help of the values from the glycemic load and glycemic index, it is easier to see which foods are problematic in this respect and which are less so.
Eating foods with a high glycemic load can promote insulin resistance. If there is insulin resistance or insulin deficiency, not enough glucose gets into the cells and the blood sugar level remains permanently high – this is referred to as diabetes.
Low-glycemic foods improve diabetes
Conversely, low-glycemic foods, i.e. foods with a low glycemic load or a low glycemic index, can improve existing diabetes again.
In a 2019 review, researchers took a closer look at a total of 54 studies on this topic. They concluded that a diet high in low GI foods had a positive effect on fasting blood sugar levels, BMI (body mass index), and cholesterol levels in people with diabetes.
The researchers write that the effects were generally small, but that drugs had only a small effect on the fasting blood sugar level.
The effects on fasting blood sugar levels were also greater the longer the studies lasted, i.e. the longer the test subjects ate a low-glycemic diet. Seven of the studies lasted longer than six months.
