Foods provide energy in the form of calories

What are the three basic functions of food and their nutrients?
(August 7, 2008)

Food nutrients are not just limited to three basic functionalities; rather they comprise energy, carbohydrates, sugars and starches, dietary fiber both soluble and insoluble, proteins, fats, vitamins and essential minerals. Foods provide energy in the form of calories. Calories act as fuel to power the system that enables the body to function. Carbohydrates on the other hand are further divided into available carbohydrate and not available carbohydrates. Foods that are categorized under available carbohydrates include sugar and starch naturally present in fresh fruits, vegetables, milk and dairy products, potatoes, cereals and bread.


Carbohydrates are converted to sugar when digested in the body, and is used as a source of energy. Unavailable carbohydrates consists of dietary fiber that cannot be digestive in the body and dust is not provide the body with any kind of energy. Dietary fiber is further subdivided into groups which are soluble fiber and insoluble fiber. Soluble fiber is available in certain pulses such as lentils and beans and specific vegetables and fruits also including oats, barley and rye. Soluble fiber is essential in reducing the blood cholesterol levels and regulating the level of sugar in the blood. In soluble fiber is found in specific cereals and grains and also in some fruits and vegetables. Since this fiber cannot be digested in the body, its basic function is to add bulk to the waste products which in turn helps an individual against bowel disorders.

Proteins are vital for the growth and maintenance of the body. It is also used to produce certain hormones and enzymes and in the absence of carbohydrates and fat, protein is also used as a source of energy. Proteins are developed from amino acids and there are 20 types of amino acids in the body. Some of these are produced in the body while others are available only through diet. Such amino acids which can be supplied only by the diet are known as essential amino acids. Foods that contain essential amino acids comprise milk and dairy products, meat, fish and eggs. Certain cereals, beans lentils and dried nuts also contain some amounts of essential amino acids.

Fat is also important in building cell membranes and is instrumental in providing vitamins such as A, E, D and K. Other important functions of at include its ability to keep the body warm during cold periods and also a shock absorbing protective layer below the skin. Fats are made from fatty acids and typically there are three types of fatty acids. These are saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids. Oils such as coconut oil, palm oil, meat products such as lard, suet etc. and milk products. Sources of mono unsaturated fatty acids include olive oil and rapeseed oil while oils rich in polyunsaturated fatty acids come from seeds and nuts such as sunflower, safflower, corn and soya. Certain components that are required in much smaller quantities include vitamins, minerals and trace elements that are essential for various functions within the body and even a slight deficiency could lead to health issues. Almost all natural foods contain a variety of these components.