The Glycemic Index shows you how quickly the carbohydrates you eat affect your blood sugar (glucose) levels. The faster the process, the greater the insulin secretion from our body, meaning you will feel hungry again sooner. This ultimately leads to a greater intake of calories per day and therefore an increase in weight. The lower your Glycemic Index is, then the longer the digested food “stays”. In general, a GI of under 40 is ideal, a GI up to 70 is acceptable in certain cases, by a GI above 70 should be avoided. Since the reference value is 100 = White bread, a GI above 100 is also possible (e.g. malt!).
Note: There are two different index systems. The more common index uses White bread = 100 as its basis, whereas the other starts from Sugar = 100. That is why on the Internet, you can find different values for the same type of food, which can lead to some confusion. The important thing is to choose just one system and to follow and use its values (the relative differences are of course the same within the respective system).