Carbohydrates provide human beings with the energy to go about their entire day and perform their daily activities effortlessly. Metabolism of carbohydrates is the process of digestion that breaks down food containing sugar into simpler units. Sugar in food is also known as saccharides. The process of digestion or metabolism begins in the mouth and, at times, ends in the large intestine. This article will discuss the metabolism and absorption of carbohydrates in human beings. In addition, we will discuss the types of carbohydrates we consume daily.
Types of carbohydrates consumed by human beings
Three types of carbohydrates are consumed by human beings daily. While some carbohydrates occur naturally, others can be found in vegetables and fruits, while refined foods mostly lack good nourishment. Starches, simple carbs and fibres are the three kinds of carbohydrates. Complex and simple carbohydrates break down into glucose at the end of the carbohydrate metabolism process. Simple carbohydrates break down into one of the two sugar molecules, while complex carbohydrates break down into more than two units of sugar molecules. On the other hand, fibre carbs are found in the healthier alternatives of food, although they don’t get broken down in the natural digestive process for carbohydrates.
Different carbohydrate-containing food items
Naturally occurring carbs include dairy and fruits. While refined, simple carbs are processed in industries that include desserts, sodas, and candies. There are good carbs and bad carbs. Good carbs include legumes, whole grains, lentils, beans, peas, and potatoes. At the same time, fibre is found in healthy carbs like fruits, whole grains, legumes and beans. People consume healthy carbs to maintain body weight. They contain more vitamins and minerals. On the other hand, refined carbohydrates are devoid of good vitamins and minerals and are also high in calories. Therefore, a higher intake of refined carbohydrates can result in type-2 diabetes, obesity and even severe heart diseases.
How many carbohydrates should a human being intake?
Dieticians advise people to consume 45-65% of carbohydrates daily. For instance, people consuming 2000 calories daily should have about 900 to 1300 carbohydrates. However, the quantity of carbs intake depends on the requirements of each individual.
Digestion of carbohydrates
Carbohydrate metabolism begins in the mouth, where the salivary amylase is secreted from the salivary glands. Whenever individuals consume food, they begin chewing, breaking down the food into smaller units. The saliva moistens the bits of food, and the salivary amylase initiates the breakdown of carbohydrates into sugar. The chewing or mastication of food is called the mechanical process of digestion.
After the food is chewed, it is passed down the oesophagus into the stomach, where the food particle is called chyme. The acid present in the stomach kills the bacteria present in the chyme, following which the next course of action takes place.
The chyme travels from the stomach to the first part of the small intestine, also known as the duodenum, where the following processes occur:
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The pancreas secretes pancreatic amylase, breaking the chyme into maltose and dextrin.
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The small intestine’s wall secretes sucrase, lactase and maltase, which breaks the different sugars into simpler sugars. The simple sugars are then absorbed in the small intestine. After absorption, they are processed by the liver, where the glucose is stored as glycogen.
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The simpler glucose is transported to the different body parts through blood.
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Insulin is released into the body by the pancreas to convert glucose into energy for the body to utilise.
Enzymes used in the digestion of carbohydrates
Several enzymes are used in the metabolism of carbohydrates, starting from salivary amylase, which is secreted by the salivary glands in the mouth. In addition, the small intestine wall secretes enzymes like maltase, lactase and sucrase, which convert chyme into maltose, lactose and sucrose, respectively.
Absorption of carbohydrates
After the small intestine converts the sugar chains into maltose, sucrose and lactose, it is absorbed by the transport proteins and sent over to the liver, where it is further broken down to be stored as glycogen. Whatever is left undigested travels to the large intestine, where bacteria and bacterial enzymes break the undigested carbohydrates into simple sugars. This breakdown results in releasing many gases, diarrhoea and gastric symptoms. The release of gases is one of the main reasons why people who suffer from lactose intolerance experience many gastric symptoms.
Conclusion
The metabolism of carbohydrates process begins in the mouth of an individual, where mechanical digestion takes place with the help of chewing. Next, the broken food particles travel to the stomach and small intestine, where they get broken down into more specific products of carbohydrates. It is finally absorbed and reaches the liver first, where it is stored as glycogen and then distributed to the rest of the body through blood. Finally, the undigested carbohydrates are digested in the colon, which results in gases and gastric symptoms.