types of Carbohydrates

Carbohydrates

Carbohydrates Definition
compound made up of carbon, hydrogen, and oxygen atoms; major source of energy for the body
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 Carbohydrates are defined as polyhydroxy aldehydes or polyhydroxy ketones or substances which give these on hydrolysis and contain at least one chiral carbon atom. It may be noted here that aldehydic and ketonic groups in carbohydrates are not present as such but usually exist in combination with one of the hydroxyl group of the molecule in the form of hemiacetals and hemiketals respectively.

Types of Carbohydrates The human body needs to maintain a definite percentage of carbohydrates intake for a healthy constitution. The World Health Organization recommends that about 55-75% of energy requirements of an adult should be met from carbohydrates. Our body needs to maintain this level of intake, failing which, there can be complications like muscle cramps, fatigue, poor mental functions and decreased resistance to diseases and ailments. There are two main types of carbohydrates, simple and complex.

Simple Carbohydrates

These are made up of a single basic sugar. Simple carbohydrates provide the sweet taste in our food. Fruit sugar, table sugar or corn sugar are all types of simple sugars. On consumption, these sugars are directly absorbed in the blood as glucose requirements of the body. Glucose provides instant energy as it reaches different parts of the body via blood. Simple sugars are occur in plenty in natural foods like fruits, vegetables, milk and milk products. In addition to these, honey, molasses brown sugar, corn syrup and maple syrup are rich sources of simple sugars.

Complex Carbohydrates

Complex carbohydrates, as the name suggests, are a combination of different types of sugars. These take a longer time to break down into their elementary form and hence, require more time for digestion. The slow break down process, supplies us with constant energy for a longer duration. Since these carbohydrates require more time for conversion, they are constantly used up by the body. Therefore, sugar converted to fat is not stored in a large quantity unlike the simple carbohydrates. Simple carbohydrates provide instant energy because these are broken down in lesser time as compared to complex carbohydrates. This increases the storage of broken down fats, which if not burned or used up, may lead to health issues.

Complex carbohydrates are abundantly found in foods like cereals, bread, pasta, whole grains, fruits, nuts and seeds.

Carbohydrates can also be classified on the basis of their chemical composition. These are the most easily available and the largest set of compounds on the Earth. Based on the complexity of their structures, there are five major classes of carbohydrates. These are described in brief as follows.

Monosaccharides

These are the basic compounds with a cyclic structure consisting of carbon, hydrogen and oxygen in the ratio 1:2:1. 'Mono' refers to single and saccharides means sugar. Glucose, fructose and galactose are types of monosaccharides.

Disaccharides

These carbohydrates mean 'two sugars', which refer to the commonly available types such as sucrose, maltose and lactose. When two monosaccharides bond together by a condensation reaction, they release one molecule of water and a disaccharide is formed. This bond is called a glycosidic bond.

Oligosaccharides

These are carbohydrates with more than two basic types of sugar molecules, usually between three and ten basic units. Their main function in the body is the storage of glucose. Raffinose and stachyose are the main types of oligosaccharides which consist of repetitive chains of fructose, galactose and glucose.

Polysaccharides

These are also called monomers and are composed of thousands of molecules of the basic units of glucose. Carbohydrates stored in the form of starch contain these type of compounds. Amylose, which is a straight chain compound and amylopectin, which is a branched compound, are the most common types of polysaccharides.

Nucleotides

It is another complex carbohydrate which contains many molecules of cyclic sugar. Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are complex five sided sugars classified under this category. The difference between RNA and DNA is that the former has one extra hydroxyl group.

Carbohydrates are the biggest source of energy in the body. Hence, their use in the right proportion is absolutely essential for the growth and well-being of living beings.