Deficiency Diseases
The main cause of deficiency diseases in our country is poverty.  A vast majority of our people are not able to buy quality food items in desired quantities.In the long run they become weak and sick.Its effect on children is more serious.

Diseases due to Deficiency of Carbohydrates:
Carbohydrates are the chief sources of energy for the body. This energy is used by the body for performing various functions.
Deficiency of sufficient carbohydrates in the diet leads to (i) body weakness, and (ii) loss of stamina, as sufficient quantity of energy is not available to the body for performing various functions. 
Diseases due to deficiency of Protein : 
Proteins are body-building food and causes serious diseases, like kwashiorkor and marasmus develop in case of children if the proteins are not sufficient in their diet. It is for this reason that the children are often advised to take a protein-rich diet – enough milk, pulses, eggs, meat and fish, 

•    Symptoms of Kwashiorkor
(i)    Protruding belly
(ii)     Dark and scaly skin, brownish hair
(iii)    Stunted growth ; usually underweight
(iv)    Swollen legs due to accoumulation of water 
(v)     Loss of appetite
(vi)     Anaemia
(vii)     Mental retardation
(viii)    Reduced resistance to diseases