We often add sugar to food and drinks to make them taste better. Sometimes we just eat it because we need to satisfy our hunger immediately and have nothing else at hand. And all the time, we consume sugar (sucrose) or its components glucose and fructose in fruits and vegetables, honey, and juices. Sugar, this simple carbohydrate, which is digested by the enzyme saccharase in the small intestine wall, is a source of readily available glucose and thus energy for the body.
It is rapidly broken down in the intestines and saturates the blood with glucose, thereby satisfying hunger and providing a resource for the work of body cells. The pancreatic hormone insulin, interacting with the appropriate receptors on liver and muscle cells, opens the transport systems that carry glucose from the blood to the cells, where it is stored as glycogen. This is how blood glucose levels normalize after a meal.
However, a sharp increase in blood glucose is not beneficial, as it changes the physicochemical properties of plasma and affects the redistribution of water in the body. Therefore, it is more beneficial for health to have a slow release of glucose into the bloodstream. This can be achieved by consuming complex carbohydrates, such as starch from cereals and cereals.
This is a hard-to-reach glucose because it requires three-stage digestion by enzymes: first in the mouth (salivary amylase), then in the duodenum (pancreatic amylase), and then in the terminal small intestine (final breakdown of the small residues of the original molecule). Since the process of assimilation is long, glucose enters the bloodstream gradually.
The glucose in the blood is gradually absorbed by the organs, primarily the brain, to provide energy to the neurons. When it becomes scarce, the hormones glucagon and adrenaline, and in a state of stress, cortisol, stimulate the breakdown of glycogen in the places of deposition, and the blood glucose content normalizes. Thus, glucose is an important energy substrate for the body, especially for the central nervous system. From the above, it is obvious that there is a whole system for regulating the amount of glucose in the blood. It is quite reliable, however, with frequent and severe fluctuations in glucose levels, these mechanisms lose their sensitivity and cease to work adequately.
It is precisely the prevention of sudden changes that is the focus of advice on healthy carbohydrate consumption.
Added sugars in drinks and foods, which require only one enzyme to digest, will quickly increase blood glucose levels and trigger insulin. As a result, the amount of glucose will quickly drop to normal. For the brain, this will look like “not enough again” and the formation of chemical intermediaries in neurons will deteriorate, they will not be able to communicate effectively with each other, which will be accompanied by distraction and cognitive decline. If fast and sharp fluctuations in glucose are repeated frequently, insulin receptors will lose sensitivity (insulin resistance), and too high blood glucose levels lead to the development of persistent memory impairment, deterioration of cerebral blood vessels and blood supply to neurons. Sharp fluctuations in blood glucose levels have a negative impact on the functioning of other organ systems.
With this in mind, a healthy diet should be dominated by complex carbohydrates and foods containing simple carbohydrates, and the amount of added sugar should be logically minimized. However, in conditions of increased energy expenditure (illness, intensive growth and maturation, pregnancy, lactation, intense mental and physical activity, emotional stress), it is critical to have a sufficient and rapid supply of glucose (from easily accessible simple carbohydrates) to avoid the formation of ketone bodies during energy production and the development of acetonemic syndrome. This is one of the reasons why children are so fond of sweets.
It quickly provides them with energy for growth and active learning.
Sugar itself is not a poison. Our body has an enzyme to break it down into vital glucose and fructose (the latter is converted into glucose in the liver). A sharp and frequent fluctuation in the amount of glucose in the blood, its deficiency or excess is dangerous. It’s up to us to avoid this. By adjusting the diet in favor of “hard-to-reach” glucose, we will not only protect the entire hormone system from failure, but also avoid the load of chemicals used in sugar refining.
So, should we eat sugar or not? I, having finished three hours of intense mental work, will go in search of some easily digestible glucose-containing goodies. Honey or raisins, or even better, dates. And if I don’t find it, I’ll put a pinch of sugar in my mouth, because I haven’t consumed the 6 teaspoons recommended by the WHO yet today.