Always Tired? The Secret Reason Might Be Hiding in Your DNA.

Tired man yawning
Cole Saladino/Thrillist

You've probably heard about early birds and night owls for ages, but are those just cute ornithological descriptions, or is there some biological truth to them?

It turns out that there's some solid physiological and genetic science behind why some people rock the mornings, others rock the nights, and a lucky few rock both. It has to do with your chronotype, a kind of biological personality that runs your internal clock. Dr. Sonia Ancoli-Israel of the UC San Diego Center for Circadian Biology talked to us about how your chronotype could be the reason you can't seem to make it to work on time, or why you pass out at 8pm after a tough day.

Early birds and night owls are birds of a different chronotype

In any work-driven society, early birds are the responsible, productive individuals who spring up in the morning and get shit done. Meanwhile, night owls are the fun party people who, if you ever spot them in the morning, are always clutching a huge coffee and reluctantly trudging along.

Turns out that these popular characterizations are related to the fact that these folks have different individual circadian rhythms. "Circadian rhythms are 24-hour biological rhythms, and there are many systems in our bodies that have these," explains Dr. Ancoli-Israel. "Recent research has shown that there are many clocks throughout our bodies, all controlled by the main clock in the brain."

That means that many of the nifty tricks your body pulls -- like changing blood pressure, secreting hormones, and regulating temperature -- happen on a schedule. Your chronotype is how your personal internal clock aligns with the 24 hours in the day, and there aren't simply two distinct personalities; you can be anywhere on a broad spectrum.

Tired woman looking for more coffee at breakfast
Cole Saladino/Thrillist

Like lots of things, it's a matter of age and genes

When it comes to your sleep-wake cycle, it's closely related to how your body temperature shifts throughout the day. You wake up when your temperature rises and get sleepy when it falls -- which is at night, and during that problematic afternoon slump, when you wish you lived in a place where siestas were customary.

"Teenagers and young adults have what we call a 'shifted' or ‘delayed’ pattern," Dr. Ancoli-Israel says. "Their whole rhythm is such that their core body temperature doesn't drop till somewhere in the late night or early morning hours, so they don't get sleepy until midnight, 1, or even 2 in the morning." The "normal" people outgrow this and become effective, functioning adults.

But what about the people with a delayed genetic chronotype? They may actually stay this way forever.

Living as a night owl in an early-bird world just ain't easy

To figure out whether you have a typical, delayed (night owl), or advanced (early bird) pattern -- see how these terms are already loaded?! -- you can take a simple quiz like this fun illustrated one.

But really, you usually just know. If you have a delayed chronotype, you're probably pretty pro at partying, because while others order vodka Red Bulls, you’re good to go with vodka sodas. Everyone congratulates you on this, but the weekdays are a problem. "These people can’t go to sleep when the rest of us do, because their bodies are just not ready to sleep. It would be like the rest of us trying to go to bed at 6 in the evening," says Dr. Ancoli-Israel. "And of course they have a very hard time getting up in the morning, when most people are getting up, because then that’' like the middle of the night for them." Getting up in the middle of the night at least five days a week?! Just imagining that is painful.

It gets worse. Night owls are more likely to be fatigued, depressed, mean, fat, and generally unhealthy, while the chipper early birds do just fine. Damn.

Woman sleeping at her computer on her desk
Cole Saladino/Thrillist 

Schedules are the problem

It's not like the gene that says you'll have a delayed chronotype also says you're going to have all these health issues. "The biggest problem these owls have is that they need to get up early to get to school or work," Dr. Ancoli-Israel points out. "They’re going to bed late, they’re waking up early... they are actually sleep deprived... and that’s why they’re tired during the day, that's why they sometimes have more depression, more anxiety, more weight gain."

She explains that night owls, constantly trying to catch up on sleep, also have "less of a routine, or standard bedtime and standard up time... a really irregular sleep-wake cycle is going to create more problems." Which makes sense, and also maybe explains why society is set up this way: it was the early birds who decided, because they were awake first. Only sort of kidding

There's hope for night owls yet

If you have the luxury of letting your body follow its own clock, great. But if you’re an extreme night owl with a standard job that forces you out of bed early, there are a few solutions for shifting your rhythm. Number one: sunlight! Especially in the morning. No sunglasses. "The mechanism of affecting our rhythm is actually through the eyes," according to Dr. Ancoli-Israel. "So when you wear sunglasses, you’re blocking all that good light." We apologize that you have to drop your cool and give up shamelessly staring at people on your way to work.

Number two: a lightbox. For those who have never seen one, try to get over the fact that a person sitting in front of a lightbox looks like a Twilight Zone scene. You don't need to just sit there though -- the doc recommends multitasking, like turning on the lightbox while you're having breakfast. You might consult with a sleep specialist about taking melatonin at night, which might help signal your body to go to sleep earlier.

What not to do? Sleeping pills. "A sleeping pill is not going to be the right answer because these people don’t have insomnia... It's just not the right time to go to bed for them!" Dr. Ancoli-Israel warns.

If you have a relatively normal (typical) or early-bird (advanced) chronotype, you aren't going to have to make these adjustments, because society is structured for you people. But you're never going to be as good at partying.

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Marina Komarovsky is a freelance writer for Thrillist and she proposes pre-party naps for delayed chronotypes who experience the afternoon slump five hours late, after happy hour. For more fun stuff on health, follow her tweets: @MariKomarovsky.