The digestive systems of birds are simple and uncomplicated but for parrots, they have a delicate system where their survival is at stake.
You know parrots are intelligent pets than can make good sounds. They can even imitate human speech as well as other acoustic sounds. Since they can perform amazing sound tricks, it is important that the owners can maintain the nutrient requirements of these birds. Too much or too little of some part of their daily food intake may be harmful to them.
Here is a good article.