You know how you'd rather douse someone with scalding-hot coffee rather than speak to them before having those first few sips of sweet, sweet brew? But once you're caffeinated, you're all ears? That could be because coffee is just as likely to boost mood as it is alertness. "In addition to blocking adenosine receptors, caffeine also affects other major neurotransmitters, including dopamine, acetylcholine and serotonin, delivering a boost even when we are well-rested," says Clow. "Dopamine improves mood, while serotonin makes us more relaxed, alert and energetic." The result is a feel-good rush from out morning coffee -- and useful information to those poor unfortunate souls who have ever dared to interact with us before we've had our first cup.

Wouldn't it be great if there were a magical elixir that helped us burn a few calories? Well, it turns out coffee may do just that. According to a study published by "Physiology and Behavior," people who drank coffee increased their metabolic rate by 16 percent over those who didn't. And as we all know, the faster your metabolism, the more calories you burn. Another bonus? Coffee has been shown to improve endurance levels, meaning if you down your cup before hitting the gym, you can potentially workout longer, and harder, which also translates into burning more calories. Just make sure to skip the cream and sugar because just like our go-to dress, coffee is most slimming when black.