It's mid afternoon and you're in need of a sugar rush to get you through the rest of the day. Why is it that after you have a taste of something sweet, just one bite isn't enough? 

TEDed recently published a short animated video describing how your brain responds to a sugar-loaded food. The ingredient essentially activates a reward system that tells your body it wants more.

"Every time any sugar is consumed, it kickstarts a domino effect in the brain that sparks a rewarding feeling. Too much too often and things can go into overdrive," according to the video.

When sugar first hits your tongue, sweet taste receptors send a signal to the brain. This signal activates the brain's reward system, a series of electrical and chemical pathways. This system is responsible for the happy feelings you get when indulging in a slice of chocolate cake. It's also the system that's stimulated by drugs -- though not nearly on the same scale.

The trick to avoid over activating your reward system? Enjoy in moderation.