Have you ever felt bogged down by fatigue after a full night’s sleep—or ready to run a marathon at one in the morning? The cause may have something to do with your diet. The video below from TED-Ed breaks down how the food we put into our bodies affects the way our brains perform. Keep in mind that cutting fatty junk food from your diet isn’t enough to keep your energy levels high. Staying hydrated and physically active can also help.