The word “breakfast” means to “break the fast.” When a person fasts, he or she goes without food. At breakfast time, you have probably gone without food for 10-14 hours (fasting) because you have been sleeping.
To function properly, your body needs food like a car needs gasoline. Gasoline gives a car the energy to run. Likewise, food gives you the energy to play and learn.
"SP472-Food Works - Breakfast," The University of Tennessee Agricultural Extension Service, SP472 5M 10/08(Rep) E12-5310-126-018-09 09-0105, http://trace.tennessee.edu/utk_agexheal/51