One recent study, for example, found that young adults who stay up late and sleep late are, on average, smarter than their counterparts who have a more traditional sleep schedule. As with those early-to-bedders, there’s an impressive amount of academic research showing that night owls are the favored ones. At this point, all the night owls should have rolled out of bed, so let’s talk about you. But before all you early risers get too smug, you need to hear the other side of this story. The combination of light and exercise helps regulate your body’s internal rhythms, meaning that you’ll sleep better and you’ll be better able to handle sleep disruptions, such as adjusting to those time changes when going on or coming off of daylight savings time. Speaking of exercise, people who do their workouts in the morning tend to stick with their routines longer and, as a result, their blood pressure is lower and they’re less likely to be obese. There also seems to be a connection between the amount of morning light you’re exposed to and your ability to control your weight–regardless of your age, how much you eat, what season it is, or how much you exercise.

Early risers are also less likely to have problems with addiction, to smoke, to drink alcohol, or to struggle with eating disorders. They’re less likely to be diagnosed with narcissism or depression or to take antidepressants. A number of studies over the past few years have found that those who get up early are generally happier than those who sleep in. Since they’ve already been up for a while, let’s start with the morning people. When you’re at the grocery store, do you want paper or plastic bags? When changing your baby, do you use cloth diapers or disposable (or compostable)? When talking about crime and punishment, do you support the death penalty or life in prison? If you’re old enough to remember the classic Miller Lite commercials, you might still be wrestling with tastes great or less filling? If you’re in the mood for a philosophical discussion with no end sight, chicken or egg? Now, even your bedtime is an issue: are you early bird or a night owl? The two, of course, are mutually exclusive–and the differences are quite stark. When picking between polar opposites, the choices we make say a lot about who we are.

A late bird might get a worm too