Owls and larks: what your body clock has to do with how you feel

There is a simple question that says more than it seems: what time would you go to bed if you did not have to get up early tomorrow?

People who come to my practice come to talk about anxiety, about a relationship falling apart or a job they cannot stand. Hardly anyone comes to talk about sleep. And yet sleep is what I have spent years studying in my other life, the university one.

I have spent more than ten years researching the relationship between the body clock and mental health. My doctoral thesis, defended at the University of Málaga in 2015, was about exactly that: personality and circadian rhythmicity in people with a substance use disorder, with and without depression.

What chronotype is, and what it is not

Chronotype is the time of day your body prefers to work. It is not a whim or a stance: it is physiology. Some people's systems switch on early and wind down early (we call them morning types, or larks), some come alive in the afternoon and evening and genuinely struggle to get up early (evening types, or owls), and most people fall somewhere in between.

It is worth saying plainly, because evening types carry a moral judgement they have not earned: whoever does not rise early is lazy, whoever does is disciplined. The hour at which your brain releases melatonin says nothing about your character.

What we have been finding

Over these years we have studied chronotype alongside the variables psychology considers protective, in samples of healthy adults. The pattern has repeated itself rather insistently.

In 2013 we published that circadian typology was related to emotional intelligence. In 2015, to resilience and optimism. In 2020, to emotion regulation, metacognitive beliefs and assertiveness. And this very year, to self-esteem, perceived social support and life satisfaction. In all of them, people with an evening profile scored somewhat lower.

Now the part that almost never survives the journey to a headline, and which to me is the important one.

These are statistical relationships, not destinies. Finding that two things travel together in a large group of people does not mean one causes the other, nor does it let anyone say anything about you in particular. There are owls with an enviable emotional life and larks who are having a genuinely hard time. If someone sells you the idea that being a night person explains your anxiety, be suspicious: the research does not stretch that far, and mine certainly does not.

The problem is not the clock: it is the mismatch

My reading, after all these years, is that your own clock matters less than the distance between that clock and the life you actually lead.

It is called social jet lag: the gap between the hours you would sleep if you were left alone and the hours imposed by work, the school run or the shift you have been given. An evening type who gets up at seven has spent years accumulating a lag not unlike crossing a couple of time zones every Monday. And that debt is not settled by sleeping until two on Saturday: it is paid in irritability, in a foggy head, and in less room to absorb life's knocks.

That is why sleep deserves a place in the conversation even when it is not the reason someone asks for help. Not to turn a relationship problem into a melatonin problem, but because when someone has spent months sleeping out of step, whatever happens to them happens with fewer resources.

What can be done about it

First: chronotype can be modified, but not the way people usually try. It has a genetic component that comes as standard and a behavioural one, and the real margin is in the second: your schedule, the light you get, when you eat, when you exercise, what time you switch off the screens. That is where the clock can be nudged, gradually and sustainably.

What does not work is willpower alone: deciding one Sunday that from tomorrow you are a six-in-the-morning person. That does not change the clock, it only adds one more list of failures confirming what you already believed about yourself.

Second, look at regularity before quantity. Going to bed and getting up at similar times every day, weekends included, does more for your mood than sleeping a lot one day and little for four.

Third is light, which is what actually sets the clock: natural light in the morning, even briefly, and fewer bright screens late at night. It is boring, over-repeated advice, and even so it is one of the few things with a measurable effect.

And fourth, when possible: negotiate your schedule instead of enduring it. Not everyone can choose their shift, but many people have more room than they think to place demanding tasks in their good hours rather than in the hours when their body is switched off.

When this stops being a matter of scheduling

Sorting out your sleep helps, but it replaces nothing. If you have gone weeks without sleeping properly, if you wake in the small hours with your mind already running and can no longer stop it, or if low mood has been installed for some time, we are no longer talking about sleep hygiene.

When it does come up, I look at it alongside everything else: what is happening to you, what you have tried and what holds up over time. The clock is one more piece — an important and much-forgotten one, but a piece.

If you have recognised yourself while reading this, we can talk for ten minutes on the phone first and see whether it makes sense to work together. With no commitment.