Carbohydrates are your body's main source of energy:
They help fuel your brain kidneys heart muscles and central nervous system.
For instance fiber is a carbohydrate that aids in digestion helps you feel full and keeps blood cholesterol levels in check.
Carbohydrates provide your body with energy. The simplest are sugars, like glucose, fructose, sucrose and lactose.
Complex carbohydrates, like starch, are made up of lots of sugar molecules joined together.
The 'identity tags' (antigens) on the surface of all cells are made from carbohydrates joined to proteins.