This is the reason why right before a test, your teacher will tell you to eat a healthy breakfast that morning. The food consumed provides the energy necessary for the flow and transfer of necessary materials to the brain and nerves. This helps you think more clearly and perform better on the test. For both animals and humans, nutrients are stored and utilized by tissues throughout the body. Most values quoted for the metabolisable Energy intake of man consists of the foods or energy yielding nutrients consumed.
Humans utilize foods from a variety of sources.
The various nutrients we derive from that food is used to maintain our body in a healthy state. The conversion of food to energy begins as soon as it enters the body. Proteins are broken down into amino acids, which are then used as the building blocks for other proteins. They must be broken down through the process of digestion into forms the body can use. Carbohydrates and lipids are also broken down into useable forms.