Monosaccharides

Fructose- found in sucrose (table sugar) and fruits. Abundant in fruit, honeys and saps.

Galactose - combines with glucose to form lactose. Rarely found outside lactose.

Disaccharides

Sucrose - made of one glucose and one fructose unit. Found in table sugar, fruit, grains and vegetables.

Lactose - made up of one glucose and one galactose unit. Found in milk and dairy products.

Maltose - made up of two glucose units. It is produced during starch digestion in the body

Polysaccharides

Digestible -Long, branched or unbranched chains of glucose molecules. Found in grains, legumes and tubers. E.g. starch

Indigestible - Long chains of glucose units, not digestible by human enzymes.

Cellulose- Found in all fruits, legumes. Resists digestion.

Pectins - found in vegetables and fruits, especially citrus fruits. Helps in holding water and forms jellies.

Hemicellulose - Primary constituent of cereal fibres.

Gums and Mucilages - Slows gastric emptying and gives satiety.

When carbohydrates are broken down, glucose is produced. It is also called as the blood sugar and is stored in the liver and muscles in the form of Glycogen and as fat in the fat tissues.

The glycogen is converted to glucose when the need arises; however the fat is not converted into glucose.

Glucose is the only form of energy that can be used by the brain cells thus carbohydrates are extremely important for the body.

Simple carbohydrates are easily digestible while complex carbohydrates take longer to digest. Complex carbohydrates like starch and dextrin have high molecular weight and are more complex than other sugars, they are not sweet and their digestibility varies.

Foods rich in complex carbohydrates are whole grains, whole wheat, oats, corn, lentils, beans, leafy green vegetables and tubers like potatoes, onions, and turnips.

When Carbohydrates are deficient in the diet, the protein is broken down to provide energy. Thus if present in the right amounts then carbohydrates spare the protein to perform other functions.

Similarly, in the case of fats too, carbohydrates in the right amounts spare them to perform their functions. If excess of fat is broken down it will result in the formation of ketone bodies, which in turn can result in acidosis.

Indigestible polysaccharides provide bulk to stools, prevent constipation and helps in peristalsis.