Jason E. Andersen

Bonus fun fact: Your brain is fueled by sugar. Well, so is the rest of your body, but your brain is especially hungry. The brain is surrounded by a series of tissues called the blood-brain barrier, which help keep out pathogens, and other bad stuff, along with large chemical molecules. Glucose, by comparison, is quite small, and can pass through this barrier pretty easily. This is why the vast majority of energy your brain consumes comes from glucose. All those neurons firing require a lot of energy and, in fact, your brain alone utilizes about 60% of all glucose in your body. So, if you have to do something that requires a lot of brain power (like taking a test), eat something sugary about a half hour before, that way your brain will be all fueled up and ready to go.