Carbohydrates

Carbohydrates are organic compounds produced by plants through photosynthesis. Having different molecular structures, they are the energy stock which the different types of plants employ for either their growth and reproduction. The only kind of carbs produced by animals is lactose, which is one of the essential parts of milk as it is secreted by the female glands of mammals; and, before the development of agriculture, it had been one of the three sources of calories the primitive hunters consumed as infant, the others being saturated fat and meat proteins. The name of these forms of organic energy, 'carbohydrate', derives from the fact that they are a complex combination of atoms of carbon and hydrogen arranged in long chains.

Plants do not make carbs for us; they are just forms of energy which they stack up to be used by them. Using sunshine, oxygen, water, and minerals, most of them make starch, which could be used for growing, or reproduction. When the plant grows up, as it becomes taller and thicker, it converts the starch in its stem and branches into cellulose (wood pulp), which is a very complex form of carbohydrates. Cellulose gives plant, especially a tree, its hardness and compactness. But a plant can also use either starch or sucrose as energy for the development of the flower, the fruit, and the seeds. And the seeds also contain starch for its development into a new plant after it has landed on the earth. Corn, wheat, and rice are cereal seeds that contain high amounts of starch.

Types of Carbohydrates

According to their molecular structures, there are three kinds of carbs: 1) monosaccharides, which are the simplest form of carbs; 2) disaccharides; and 3) polysaccharides, which are the most complex form.

1) Monosaccharides include glucose, fructose, galactose, and dextrose. They are the simplest forms of carbs because they cannot further be broken down into simpler molecules by hydrolysis. Glucose is found in some fruit, honey, and in our body; the glucose in our bloodstream is obtained when a molecule of starch or sucrose is broken down by the enzymes amylase and sucrase respectively. This simple form of sugar is used by our cells as fuel to produce ATP. Too much sugar in our blood is toxic for our tissues, as it has to be lowered through insulin, if not, we have diabetes. This does not happen when we eat fat (butter/tallow), which was the main source of energy of our ancestors (hunters) long before the development of agriculture.

2) The most common molecules of disaccharides are sucrose (table sugar) and lactose, which is present in milk. The mill industry obtains table sugar (C12 H22 O12) from either sugar cane or beetroot, both of which contain high amount of sucrose in their juice. When we eat a cake, we eat sugar, which is broken down into glucose by the enzyme called sucrase.

3) Starch and cellulose are polysaccharides, which are long-chained carbs. However the latter is even more complex than the former. This is the main reason why we can only digest starches as we do not have any enzyme to digest cellulose, which is the wood of trees and the pulp of plants.