"Stress isn't just something you feel in your head. It's something that trickles all throughout your body. Under stress, your body produces two hormones: adrenaline and cortisol. Adrenaline is like lighter fluid, and cortisol is like charcoal; the former quickly burns off the immediately available sugar in your blood, so you can fight or flee whatever is stressing you. Cortisol continues to fuel the fire, pumping more sugar into your blood so you have energy to burn. "