Carbohydrate- Composed of Carbon, Hydrogen & Oxygen hence the name "carbo-hydrate". They play important roles in fertilization, energy, immune system, blood clotting, and development and are broken down into 4 chemical groupings:
Simple Carbohydrates-
- Monosaccharides- Glucose, Ribose (ATP, NAD, FAD, RNA). They are the major source of fuel for the metabolism. When not in use, they are stored as glycogen/ polysaccharides, especially in the liver and muscle cells.
- Disaccharides- Sucrose (table sugar), Lactose (milk).
Complex Carbohydrates-
- Oligosaccharides- Frucstose (Fruit), Vegetables, Starches.
- Polysaccharides- Fiber, Storage of energy (starch and glycogen)
Am I turning you off with all of this organic chemistry? It will be tough to follow along, but we have a weight loss mystery to solve! We know the basics of a carbohydrate, now let us elaborate on glycogen.
Glycogen-Is the secondary form in which unused (glucose) energy is stored and most commonly stored in the liver and in our muscles. Our primary storage of energy is found in adipose tissue, or fat. How much glycogen is stored depends on how much we eat, work out, our eating habits, and our basal metabolic rate.
One thing to consider is that a carbohydrate consists of water, remember the root of the name we discussed earlier? Ever wonder why crash diets work (temporarily)? When you deprive your body of carbohydrates you are also dispelling water. The significant amount of weight that you watch drop abruptly is mostly composed of water. This is also why whenever you dismiss the unrealistic diet and begin eating normally, you immediately gain all of the water weight back (if not more).
Another important contributing factor in the consumption of carbohydrates is the Glycemic Index. Every carbohydrate has been graded its own number on the glycemic index which indicates the level at which insulin rises. The higher the GI (glycemic index) the higher the rise of insulin. When our insulin rises abruptly, it also drops abruptly, very similar to a caffeine binge. After our insulin levels substantially spike & decline, they create a desire for more of the same types of foods and often leave us very hungry. When choosing carbohydrates that are lower on the GI, we will benefit with a higher level of satiety, therefore not making us want to eat as much.

Below is a chart of different types of foods and their GI.

Of course not all carbohydrates are equal or bad for that matter. I think it is safe to say that vegetables are very essential to our overall health and we can benefit greatly by consuming them. Vegetables are a carbohydrate, so to say that all carbohydrates are bad would be a lie. It is also important to note that not all fruits are equal, some fruits are loaded with sugar and much higher on the GI.
I still feel all this research is ambiguous, we are going to have to dig deeper. Next time we will elaborate on the functions of proteins and fats.
'Carbohydrates are not necessary building blocks of other molecules, and the body can obtain all its energy from protein and fats.[11][12] The brain fats contain 37.8 kilojoules (9 kilocalories) per gram. In the case of protein, this is somewhat misleading as only some amino acids are usable for fuel.'-wikipedia
Sources:
wikipedia.com