Carbohydrates are also called saccharides (sugars). They consist of carbon, acid and hydrogen atoms and are a collective term for various sugar compounds. Carbohydrates are one of the main nutritional components, along with proteins and fats, and above all provide energy for the daily demands to which our body is exposed.
When walking, running, breathing, sitting and doing sports, carbohydrates ensure that new energy is constantly available for the muscles. In addition to providing energy, carbohydrates are also responsible for stability and structural maintenance in cells, tissues and organs. One gram of carbohydrate provides 4.1 kcal (kilocalories) of energy and is quickly available compared to fat and protein.
Carbohydrates are stored in our body as glucose. The main storage sites are the liver with about 140 grams and the skeletal muscles with up to 600 grams. The various carbohydrate-containing foods can be distinguished according to their glycemic index (GI), which provides information about the rate of absorption of carbohydrates from food.
The higher the glycemic index, the more carbohydrates can be ingested. Carbohydrates are also used in many other everyday products. They can be found in adhesives and film rolls.
Chemistry
Carbohydrates are, along with fats (lipids) and proteins, one of the three main nutrients for the human body. They can be divided into simple sugars (monosaccharides) and multiple sugars (polysaccharides); the latter are composed of the former. The most important monosaccharides for humans are Compounded in certain combinations, they form disaccharides such as The polysaccharides, in turn, consist of a much larger number of complexly linked monosaccharides.
In plants this storage form of carbohydrates is called starch, in meat (and accordingly in the human body) glycogen. The only difference between the two is the way the monosaccharides are linked to each other. If carbohydrates are taken in with food, they must first be broken down into their monosaccharide components before they can be absorbed into the bloodstream.
The fact that this step is omitted in the intake of monosaccharides is the basis for the wisdom “Dextrose goes directly into the blood“. The decomposition already begins in the oral cavity in the form of the enzyme amylase contained in saliva. The breakdown continues in the intestinal tract before the monosaccharides are transported from the inside of the intestine through the cells of the intestinal wall into the surrounding blood vessels, from where they can be distributed throughout the body.
Carbohydrates therefore only enter the body cells from the blood in the form of monosaccharides. There are essentially three possibilities here: Either the molecules are used as building blocks, for example for the sugar molecules on the surface of the red blood cells that determine the blood groups, or they are used to produce energy – in this case they can either be broken down directly into ATP, the body’s energy unit, or they can be combined to form glycogen, the body’s carbohydrate storage form. The latter occurs when there is a surplus of nutrients and the resulting glycogen can then be broken down again later as required and its individual parts used to produce ATP.
- Glucose (dextrose)
- Fructose (fruit sugar)
- Mannose
- Galactose (milk sugar).
- Maltose (two glucose molecules)
- Sucrose (glucose + fructose)
- Lactose (glucose and galactose).
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