Carbohydrates, also known as carbohydrates, glucides or saccharides, are molecules whose structure is composed of carbon, oxygen and hydrogen and whose main function is to provide energy to the organism, since 1 gram of carbohydrates provides 4 kcals, constituting 50 to 60% of the diet.
Some foods containing carbohydrates are rice, oatmeal, honey, table sugar, potatoes, among others, and can be classified according to the composition of their molecules in complex and simple carbohydrates.
Functions in the organism
Carbohydrates are the main source of energy for the organism because during their digestion glucose is generated, being this the preferred fuel for the cells of the organism, since they degrade this molecule and ATP is produced, which is used in the various metabolic processes for the proper functioning of the organism. Glucose is mainly used by the brain, using 120 g per day, which represents the majority of the 160 g of glucose that the body needs daily.
In addition to this, a part of the glucose generated is stored in the form of glycogen in the liver, and a small portion in the muscles, due to possible eventualities in which the organism needs to use this reserve as may occur in situations of prolonged fasting, alert or metabolic stress, for example.
The consumption of carbohydrates is also important for the preservation of muscles, since the lack of glucose will favor the loss of muscle mass. Likewise, fiber is also a type of carbohydrate, which despite not being digested into glucose, is essential for the digestion process, as it decreases cholesterol absorption, helps maintain blood sugar, increases bowel movements and favors an increase in stool volume, avoiding problems such as constipation.
Is there another source of energy besides glucose?
Yes, when the body uses the glucose reserve and there is no (or very little) carbohydrate intake, the body begins to use the body’s fat reserves to generate energy (ATP), replacing glucose with ketone bodies or ketones.
Classification of carbohydrates
Carbohydrates are classified according to their complexity into:
Simple carbohydrates or also called monosaccharides, are simple units or molecules that when joined together form more complex carbohydrates, these are glucose, ribose, xylose, galactose and fructose. When a portion of carbohydrate is consumed, this more complex molecule will be broken down in the gastrointestinal tract until it reaches the intestine in the form of monosaccharides to be absorbed.
The union of two monosaccharide units form disaccharides such as sucrose or table sugar (glucose + fructose), lactose (galactose + glucose) and maltose (glucose + glucose), for example. In addition to this, the union of 3 to 10 monosaccharide units give rise to oligosaccharides.
Complex carbohydrates or polysaccharides are those that contain more than 10 monosaccharide units, forming complex molecular structures that can be linear or branched, some examples are starch, glycogen that is stored in the liver and cellulose.
Within complex carbohydrates is fiber, which are components of vegetables that are not digested by gastrointestinal enzymes, some examples are cellulose, fructooligosaccharides (FOS) and lignin.
What are carbohydrate foods
Some carbohydrate foods are bread, pasta, rice, wheat flour, cornmeal, toast, beans, chickpeas, lentils, corn, barley, oats, cornstarch, potato, sweet potato, yam, okra, and cassava.
Excess carbohydrate is deposited in the body as fat, so although they are very important as our body, you should avoid abusing them, on average it is recommended intake between 200 to 300 grams of carbohydrates per day, an amount that varies according to weight, age, sex and physical activity performed by the person.
Learn more about which foods contain carbohydrates.
Metabolism of carbohydrates
Carbohydrates have several metabolic pathways that can be used to metabolize carbohydrates and carbohydrate metabolism.These are:
These metabolic pathways are activated depending on what the organism requires and the situation in which it finds itself.