Carbohydrates help maintain the glucose level and thus give them the energy to maintain those metabolic reactions. Proteins are essential for repairing body tissue, reproduction, and give resistance to infection. A deficiency of proteins can result in poor feather quality. Fats give them energy, but much like humans, too many fats can cause them to become overweight. Birds require thirteen essential vitamins and you will notice that many diets are fortified with vitamins.
Water is very important.
They can survive longer without food than they can water. It is important to always have a fresh source of water. It is always important to feed fresh food and water because it can become contaminated with droppings and cause an infection. There are two basic diets, those being seed diets and softbill diets. Seed diets are more common because most common pet birds require seed diets.