Yes, it's about evolution. Carbohydrates gave us energy, but refined carbohydrates such as sugar did not exist, so there was no harm to health, as the fiber removed during the refining process slowed down the absorption of carbohydrates. Sugar itself is not harmful. Dates, for example, are solid sugar. But fiber and other phytoelements in dates slow down the absorption of sugar and optimize glycemic control, from which there is no excessive increase in glucose in the blood, leading to a physiological stress response.
(I wrote a little crookedly, but I was too lazy to correct ...)
Rather, because there is not so much of it in natural products, if, for example, do not take into account the South African and Asian fruits that came to us later. the more receptors. the brighter the taste. When a person consumes a lot of carbohydrates and sweets, in fact, they become dull. When you are left without carbohydrates almost at all. After a month, the pumpkin will seem very sweet to you, and the sweetness of some fruits will simply start to pinch your tongue. Rettors increase their sensitivity as needed.
Sugar is useful as a source of easily digestible energy. If we are talking specifically about sucrose (fructose, glucose and a number of other sugars are also sweet), then it breaks down into fructose and glucose, and glucose is vital . If there is no external supply of glucose, your liver will begin to produce it. And if there is too little glucose in the blood (hypoglycemia), a person gets tired easily, at an even lower level - he loses consciousness and may die. Diabetics should definitely carry a sugar cube or something containing sugar in order to quickly eliminate hypoglycemia when they notice its symptoms, or to prevent it after exercise. Moreover, it is sugar or glucose that is needed, not starch or fats, which will have to be digested and broken down for a long time, and then the glucose itself is synthesized.
The body (and taste buds, in particular) is "sharpened" by natural selection for FORMER living conditions when there were not enough calories and people were physically active . If you do not overeat and are physically active, then sugar will not harm you in any way (except in rare cases of congenital diabetes.) If you overeat and are inactive, you can get not only obesity and other problems (with joints, heart, etc.), but also diabetes and hyperglycemia (high blood glucose): even if there is no sugar in the diet. And if you already have diabetes, or if you are dealing with it, then the "extra" sugar becomes more dangerous than other "extra" calories, since it directly and instantly supplies all its glucose into the blood (where there is already too much of it). So it's not "bad" sugar to blame, but your laziness and gluttony over the years. If you earned money by unloading the carriages by hand (or you got food by running after the deer for hours with a spear in your hands - until the deer are exhausted) and at the same time were chronically malnourished, then sugar would only do you good. And even three liters of Coca-Cola in one sitting or a couple of liters of ice cream would not do anything to you. Move and do not overeat, then sugar in any form will not harm you.
Evolution is slow (in the scale of human life). The way food is obtained and processed has changed dramatically over the past thousand years. Once upon a time people did not have enough food not only for children, but for themselves. Everyone was starving. Sugar was quite common, although not the most energetically beneficial or useful product. Many fruits contain it. Whoever could recognize sweet food among just fiber - won, survived. The centuries passed quickly, the receptors remained. That's the whole story.
Sugar = energy. Accordingly, sweet - more energy than not sweet.
As a result of Natural (thank Darwin) Selection, those ancestors of man had an advantage (by the way, not even hominids or the first Homo, perhaps an increase in the number of sweet receptors occurred in some of the first mammals, also our ancestors), who could choose the most energetically beneficial (nutritious) food, for example, from a variety of fruits or tubers (potatoes), choose a little sweeter, nutritious, ripe than the rest. And such a skill is possessed by individuals that have a larger number of corresponding receptors than their counterparts in survival and translation of their genes into the future.
In the conditions in which our ancestors evolved in us (namely: life in the savannah - biocenosis not too abundant with nishtyaks, serious intraspecific competition, a couple of global cold snaps, lack of smartphones and zekveschen), and also taking into account the long time from the appearance of the first hominids to the present moment (at least 5-6 million years), we have: one successful reception, more nutritious, than a neighbor's, kartochi, can save the life of you, your woman, your children, and then their children ...
And thus, if "everyone died, and I stayed" (because I chose the most sweet fruit and did not freeze / starve), then your genes, and with them the increased number of sweet receptors, will be passed on to most of your descendants.
And in this way, sadly and joylessly, amid the deaths of close and dear people, generation after generation, over millions of years, Mankind forged its love for chocolate bars.
But not it's sugar: I saw the result of a study that showed that the most delicious foods for us and their combinations are most often extremely nutritious, for example, the calorie content of the mix "fats + carbohydrates" provided us with a love of chips, which are the very essence of fats and carbohydrates (oil which is fried + the aforementioned potatoes).
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