Carbohydrate, protein, fat, vitamins, mineral salts and fiber are what makes a balanced diet must contain. These things should be present in appropriate proportions. This tells that balanced diet takes into consideration a diet that meets ones nutritional needs and on the same side not providing any excess nutrients.
On the other hand an unbalanced diet can cause problems with maintenance of body tissues, growth and development, brain and nervous system function, as well as problems with bone and muscle systems.