What’s Your Chronotype? Find Out What Your Unique Sleep Personality Reveals About You and Your Health

Key Takeaways:

• Your chronotype is whether you’re a night owl, a morning person, or somewhere between the two. It’s your unique expression of a circadian rhythm.
• Chronotypes are determined by a combination of genetics, age, and exposure to light. Although chronotypes may shift throughout one’s lifetime, they typically remain stable in adulthood.
• Scheduling sleep, exercise, and even your diet around your chronotype can help you make the most of your days—and nights.

Related Studies:

• TIME-ZZZ: Contribute to advancing our understanding of the connection between sleep and biological aging. Anyone who has ever taken  an Index test registered through Elysium Health is eligible to participate in this study. Learn more here. 

Have you ever wondered why some people are night owls, staying awake until the wee hours of the morning, while you can barely keep your eyes open past 9:00 p.m.? Or why you’re super productive in the early morning but can’t get much done later in the day? There’s a science behind it: your chronotype. In short, a chronotype is your body’s natural preference for sleep and wakeful times. It determines when you’re most tired and when you’re most alert and active. It’s also referred to as your diurnal preference. In addition to sleep, your chronotype also influences your appetite, body temperature, mood, and exercise habits.

So, what’s your chronotype, and how can you use it to your advantage? We break it down below.

Chronotype vs. Circadian Rhythm

You’ve likely heard the term circadian rhythm. It refers to the body’s internal master clock, located in the suprachiasmatic nucleus (SCN) of the hypothalamus in the brain. This clock dictates physical, mental, and behavioral processes within a 24-hour cycle. Our sleep-wake cycle is a circadian rhythm that’s influenced by light. When the sun sets, our body knows it’s time to rest. It releases melatonin, a hormone that makes us sleepy. When the sun rises, the brain gets a message that it’s time to wake up and be active.

So, how is this different from a chronotype? A chronotype is your personal expression of a circadian rhythm. Researchers have noted variations from person to person with the circadian rhythm, which they call morningness or eveningness—whether you’re a morning person, a night owl, or somewhere in between.

Researchers have identified three main chronotypes: 

• Morning-types (M-types): People with this chronotype are also known as morning larks because they like to wake early and feel most alert and active in the first part of the day.
• Evening-types (E-types): Night owls have a delayed sleep phase and feel more active late in the evening or night. They also awaken later in the day.
• Intermediate (or N-types of neither): These people have no clear type. Research suggests that 60 percent of the population is intermediate, with the other 40 percent representing the other two types.

Emerging research suggests a fourth chronotype: bimodal, which shows preferences toward both morningness and eveningness. In a study in Chronobiology International, bimodal types answered questionnaire questions as M-types in some questions and E-types in others.

So, What Determines Your Chronotype? 

Sleep expert and Elysium Scientific Advisory Board member Russell Foster, Ph.D., professor of circadian neuroscience and head of the Department of Ophthalmology at the University of Oxford, says three factors influence chronotypes:

• Genes: There is a genetic component behind chronotypes. Research in the study Sleep found nine “clock genes” that influence the chronotype. One of the most studied clock genes is PER3, which is associated with morningness, those who wake up and go to bed early.

• Age: Your chronotype can shift with age. For example, babies and young children tend to be early risers, while teens and young adults favor sleeping late (and going to bed late). From age 10, there is a tendency to go to bed and wake up later, which peaks in the late teens and early 20s (women peak earlier than men). Then, according to research, we adopt a morning chronotype as we age,  and your chronotype typically remains stable through adulthood.

•  Light: Light exposure at dawn or dusk can influence your chronotype, according to Foster, who authored a study in Chronobiology International on university students worldwide. The study revealed that the later “night owl” chronotypes detected less morning light and more early evening and dusk light.

How Do You Figure Out Your Unique Chronotype?

Sometimes, it’s obvious; you’ve always been a night owl and are more productive or active in the evening. Or you’ve always been an early riser. If you’re not sure what your natural inclination is due to, say, work schedules, you can track your sleep and wake times to see a pattern emerge, paying particular attention to the weekends and vacations when you don’t have to get up early for work or use an alarm clock. Also, note the periods of the day when you’re feeling most energetic and productive.

You can also take online quizzes and assessments to figure out your chronotype. If you are an Index user, you can enroll in Elysium’s sleep and aging study, TIME-ZZZ, to learn your chronotype and if there is a mismatch between your sleeping pattern and chronotype, which could result in “social jet lag.” Learn more about TIME-ZZZ below.

Why It’s Important to Know Your Chronotype

Being out of sync with your circadian rhythm and chronotype can cause sleep disturbances and affect your overall health. A recent study in Metabolites suggested that circadian misalignment is associated with an increased risk of metabolic disorders, cardiovascular diseases, obesity, and poor sleep quality. 

Once you figure out your unique sleep-wake pattern, you can use it to maximize sleep quality and get the most out of your day, boosting productivity, workouts, and your mood. Use your chronotype to:

• Set a realistic bedtime: Rather than fighting your natural rhythm, fall asleep at a time that feels right to your body.
• Boost productivity: Schedule work, creative time, and important meetings when you’re naturally more productive.
• Meal plan for your chronotype: Research has shown that those with an evening chronotype consume more calories and fat, especially at night. They also had less vegetables and fruits but more caffeine and alcohol. Other studies have shown that evening chronotypes may consume less protein, calcium, zinc, magnesium, riboflavin, and vitamin B6. You may not be able to change your chronotype, but you can change your eating habits to make healthier choices and take a supplement to compensate for any nutritional gaps. Eating at consistent times throughout the day can also help keep you in alignment with your circadian rhythm.
• Factor in fitness: Schedule workouts for when you feel most active. Morning types do best with an early workout. Intermediates benefit from afternoon workouts, while late types perform best in the evening. Studies have shown that evening types log less physical activity and experience more sedentary time. Prioritizing an evening workout can offset sedentary behavior.
• Manage your mood: Studies have shown that the evening chronotype is more at risk for depression, and poor sleep quality may play a role. Prioritizing sleep and developing healthy sleep hygiene, such as creating an environment that encourages shut-eye (dim lights, cool temps, no screentime, etc.) and a consistent bedtime routine, may help boost your sleep and mental health. (Speak to a mental health provider if you are experiencing depression.)

Going Against Your Type

In an ideal world, you can schedule your life around your chronotype, but that’s not always possible. Let’s say you’re a night owl but have a job that requires an early start, or you’re a morning lark who must work a late shift. Now what? When we can’t control our schedule, there are a few ways to gently adjust your sleep-wake schedule:

• Work with light: Not a morning person? Exposure to sunlight first thing may help you wake up and make you sleepier earlier in the night. Conversely, if you need to sleep later in the morning or during the day due to a night shift, invest in blackout shades to keep the room dark during daylight hours.
• Switch your workout: Studies have shown that adding low-intensity exercise in the morning can help you adjust your circadian rhythm if you’re a late chronotype.
• Time meals right: If you’re an evening type and struggle with falling asleep at a decent hour, set up your meals so that dinner is your lightest one, about two to three hours before bed. Digesting a heavy meal late at night can interfere with sleep.

Help Elysium Understand the Science of Sleep

Introducing the Translational Initiative to Map Epigenetics in Sleep (TIME-ZZZ), a new study designed with sleep expert Russell Foster, Ph.D., to help us better understand the connection between sleep quality, chronotype, mental health, and biological aging. 

If you’ve ever taken an Index test registered through Elysium Health, you can participate by answering a series of short questionnaires (called activities) covering topics on sleep quality and mental health benefits. Participants get the following perks: 

• Enjoy a special webinar with Dr. Foster focused on the science of sleep. You can register for the webinar here.
• Receive study insights and contribute to advancing clinically validated interventions and health monitoring tools for longevity