Functions of food
Food is important for life. To be healthy and active, we should certainly have enough food. The food we eat should be safe and rich in all the nutrients for our body needs. We should choose from a wide variety of foods and we should eat them regularly, every day. Do not forget that we should also enjoy the food that we eat; it should look, smell and taste good. Without good nutrition, children and young people cannot develop their potential to the full and adults will have difficulty in doing their best.
Food provides our body with what they need to
* Stay alive, be active, move and work;
* Build new cells and tissues for growth;
* Stay healthy and heal themselves;
* Prevent and fight infections.Foods are classified according to their functions in the body. The functions of food can be broadly classified into three main categories.
Physiological functions of food
The physiological functions of food can be further sub-divided as follows:
a. Energy giving
b. Body building
c. Protective and Regulatory
a) Energy giving
This group includes foods rich in carbohydrate, fats and proteins. Energy is defined in terms of kilo calories and thus one gram of carbohydrate gives 4 kcal, one gram of protein gives 4 kcal, while one gram of fat gives 9 kcal.
This group may be broadly divided into two groups:
* Cereals, pulses, nuts and oilseeds, roots and tubers.
* Simple carbohydrates like sugars, fats and oils.Cereals provide in addition to energy large amounts of protein, minerals and vitamins in the diet. Pulses also give protein and B vitamins besides giving energy to the body.
Nuts and oilseeds are rich in energy yielding as they are good sources of fats and proteins. Roots and tubers though mainly provides energy, contribute to some extent to minerals and vitamins.
b) Body Building:
The foods we eat become us. Thus one of the most important functions of food is that of building the body.
They are classified into two groups:
* Milk, egg, meat and fish: They are rich in protein of high biological value. These proteins have all the essential amino acids in correct proportion for the synthesis of body tissues.
* Pulses, oilseeds and nuts: They are rich in protein but may not contain all the essential amino acids required by the human body.
c) Protective and Regulatory function
Foods rich in protein, vitamins and minerals have regulatory functions in the body eg. maintaining the heart beat, water balance and body temperature. Protective foods are broadly classified into two groups.
* Foods rich in vitamins, minerals and proteins of high biological value eg. milk, egg, fish and liver.
* Foods rich in certain vitamins and minerals only eg. green leafy vegetables and fruits.