What’s your chronotype and can you change it?

Liz Hollis 22 March 2022

We've all heard the phrases night owl and early bird, but have you actually stopped to find out exactly what your sleep type is? 

Some wake at dawn, refreshed and ticking off most of their to-do list by 9am. Others need a repeat alarm clock and strong coffee to shake off morning grogginess and then think nothing of staying up long past midnight.

Most of us fall somewhere in between but still with a distinct preference for mornings or evenings.  

The times when you feel most tired or more awake is all down to your individual body clock or “chronotype”. Science is now revealing that that this is pretty much hardwired into you from birth—to such an extent that a new blood test may soon be able to identify your individual patterns. 

“We all have a different propensity to sleep and a preference for what sleep researchers call ‘morningness’ or ‘eveningness’,” says sleep scientist Dr Charlotte Edelsten.

“This is our chronotype and it is determined by a gene called PER3 “Unfortunately, you can’t change this as it’s genetic.”

So, give up the battle to control your body clock. Instead, identify your personal chronotype and embrace it, because how you manage your body clock can have a profound effect on your health and wellbeing.

Work with, not against, your natural body clock

It’s not your fault if you are allergic to early mornings or run out of fizz by lunchtime. Stop trying to push through your natural tendencies and learn how to work with your inner rhythms instead.

Modern life triggers, such as smartphones, travel, late night snacking and shift work, can distort our internal sleep signals—which is why it’s never been more important to understand exactly what time your personal body clock is set on.

A recent study from the University of Colorado, in the Journal of Biological Rhythms, suggests that your chronotype may even influence everything from your chances of depression, diabetes and heart disease to the optimal time for exercising, eating or taking medicine.

A central “master clock” in the brain helps regulate our body through a 24-hour cycle, deciding when you need sleep.

The body has its own timetable. Temperature, concentration, strength, adrenaline, stress-beating hormones, hearing, manual skills and even our athletic performance all vary with the time of day.

Four main chronotypes

Most people’s sleep-wake cycles vary by four to six hours. There are several chronotypes and research tests can identify exactly which one you are and what time your natural bedtime is. However, Dr Edelsten says that most of us fall into one of the four main types.  

Morning: You don’t find it difficult to get up and out and you tend to be most energetic and productive before noon. You tend to wake super early in the morning and feel alert. Most productive before lunch.

Evening: You are definitely not a morning person. You feel groggy first thing and your energy increases through the day, peaking from noon—sometimes even later if you are an extreme version. You’ll probably feel most productive and energetic between 2 and 4pm but you may have bursts of energy later.

Solar: You’re somewhere between the Lark and Owl and you just prefer to get up when it gets light and wind down as it get dark at night. Most people fall into this category. Your cycle is aligned with the sun. You tend to wake when it gets light so find it easier to get up in the summer. You are likely to feel most productive in the morning and your energy tails off through the day as you wind down early evening.

Unsettled: You may experience insomnia and disturbed sleep, making it hard to work out when you feel most awake. The time you feel most alert may change and is hard to pin down. 

How to work out how your body clock is set

Blood test: An exciting new blood test for your body clock is on the horizon. Scientists at the University of Boulder use a method called metabolomics assessing levels of 4,000 different biomarkers in your blood, including amino acids, vitamins and fatty acids. They use an algorithm to detect which biomarkers are linked to different chronotypes. Researchers say they can envisage a day where we have a blood test to find out how our personal clock is set.

DIY assessment: Ask yourself what time you would ideally get up and go to bed if you were free to choose to reveal your natural rhythms. You can also consider when your personal “power hour” is—the time when you feel and perform at your best. Work this out by considering whether you would prefer to do a difficult exam at 7am (Lark) or 10pm (Owl), somewhere in between (Solar) or it changes according to how much sleep you’ve had (Unsettled).

Online questionnaire: Sleep researchers have several computer tools they can use. One is called the Morningness-Eveningness (MEQ) test and has 19 multiple-choice questions about your daily habits, such as how well you think you’d perform if you had to exercise with a friend at 7am. You can find plenty of these tests online, such as the AutoMEQ by the Center for Environmental Therapeutics. Sleep scientists Dr Michael Breus of Sleep Doctor has devised the chronoquiz to help you decide what you are.

Laboratory test: Doctors can measure our chronotype accurately by performing what’s called a “dim-light melatonin assessment”. You stay in dim light for 24-hours and every hour doctors take a saliva and blood sample and measure how much of the sleep hormone melatonin it contains. Plotting how it changes will show when you would naturally sleep and wake.

Why you need to know your chronotype

 

Understanding your type can help you know the optimum time for different activities—reducing guilt if you’re someone who finds it hard to get up or understanding and forgiving yourself if you simply hate parties that carry on after 9pm.

Work out your type to make the most of your day. Dr Michael Breus says that you don’t just get to pick which chronotype you want because they are genetic so it’s all about acceptance. “You don’t need to change it—you just need to embrace it!” he says.

Plan your day around your type. “You are programmed to perform far better at certain times through the day and less well at other times. A better understanding of your own biological coding will help you work with your body rather than against it.”

Harnessing your inner clock can help you wake up more alert, reduce insomnia, schedule activities at the best time of day for you. It can also help you adapt to external events you can’t do anything about, such as shift work or early meetings.

In the future doctors may be able to help us work out to the optimal time for activities like brain-power tasks or taking medication. Mounting research suggests it can influence everything from your predisposition to diabetes, heart disease and depression.

How to manage your body clock

While you can’t change your type, there are lots of time cues, that scientists call zeitgebers, that can help you manage it. For example, if you’re an extreme night type who has an early meeting.

Light: Light will help wake you up, so ensure you get as much as possible when you need to feel more awake. If you are an evening type step outside in the daylight to wake you up. Use a medical lightbox for around 30-minutes. Make sure you are close to the box to ensure it works properly.

Exercise: Stimulates your system and boosts the hormone cortisol, so do it whenever you want to feel more awake. Most Olympic records are broken between 4pm and 7pm and this isn’t down to chance. Most people peak physically then with body temperature highest and muscles at their most flexible. So, monitor your own body to work out where it falls in this time slot and schedule physical tasks or exercise accordingly.

Eating and drinking: Eat when you want to feel more awake and don’t eat late at night if you want to fall asleep earlier. “Food and drink is a crucial zeitgeber,” says Dr Edelsten. “Eating is one of the ways our body works out what time of day it is. So, if you’re a night owl and you want to sleep better, eating a pizza at 10pm won’t help because it stimulates digestion. Heart rate rises and your body thinks it’s time to wake up.”

Use an app: Nurture your rhythms with the help of apps designed to manage your circadian rhythms. The new Shift Work App will give you personalised advice, such as when to avoid light, to help your body clock adjust when needed. My Circadian Clock, from the Salk Institute, can track your food, drink, exercise and sleep to help you manage your inner clock.

Temperature: Our body temperature increases slightly through the day to a peak, then declines as we grow sleepy, dipping in the middle of the night. Turn down the heating and avoid becoming overheated when you want to encourage sleep and the opposite when you want to promote wakefulness.

Social interaction: Makes us feel more awake. Stimulate yourself when you need by talking, laughing and chatting with others and avoid social situations when you want to wind down.

Routines: If you have to do certain activities at certain times doing shift work, for example - a strict routine can help you cope. Eat, sleep, exercise, go outside in the light, rise and go to bed at the same time every day and it will help you deal with that enforced 9am start to the working day—even if you’d rather start at 11am!

Work and play flexitime: Most work is roughly 9am to 5pm so it can be tough if you peak later than this. If this doesn’t work for you, try to find work or hobbies that are more flexible.

Read more: 6 Books that work better on audio

Read more: Sleep: How it changes as you age

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