Corn syrup and corn sugar, also called dextrose or glucose, are popular because their sweetness and thickness can be regulated. They also prevent moisture loss and extend the shelf-life of the food. The primary sources of sugar are sugar cane and sugar beets. While sucrose is a component found in cane sugar, beet sugar, fruits and vegetables, in its purified isolated form it is commonly found in manufactured foods. The natural sugars found in whole fruits, vegetables and grains are bound to essential vitamins, minerals, fiber, and oils.
Enzymes are also present in whole plant foods.
These aid in the metabolic process necessary for digestion of the sugars. In addition, the sugars in natural whole foods arrive in the body diluted in a large volume of water to assist in its metabolism. Extraneous concentrated sugars contain empty calories that can be converted to energy, but provide no valuable nutrients. It merely enhances the flavor of many bird foods and makes them more palatable. Sugar is known to cause dental caries in humans because sugar encourages the proliferation of oral bacteria.