Why do people say that we should have a big breakfast and a small dinner?

Thank you for using the Jiskha Homework Help Forum. Think about your car and filling it up with gasoline, etc. before you take a long trip. You need energy to run on as you begin your day. During the day you will be burning off the calories. At night if you eat a huge meal right before you retire, not only will you not burn off the calories but you may have indigestion. If you look in any health text you will also see detailed reasons for this.

what does your system do?