Why am I always tired? Sleep, mood and stress causes to check

Feeling tired all the time usually comes down to one or more of four things: not getting enough good sleep, low mood or depression, long-running stress or burnout, or a physical cause such as an illness or a medicine. The kind of tiredness you have is the best clue. Nodding off during the day points to sleep, feeling wired but exhausted points to stress or insomnia, and a heavy, flat tiredness that sleep doesn’t fix often points to mood. Because physical causes are common too, tiredness that has lasted a few weeks is worth checking with a doctor.

Are you sleepy, or tired in a different way?

Start by working out whether you’re sleepy or fatigued, because they point in different directions. Sleepiness means your body is trying to fall asleep: your eyes close while reading, you drift off in front of the television, you fight to stay awake in meetings. Fatigue means you feel drained, heavy or worn out, but you might not be able to nap even if you tried.

Many people tick more than one row. Poor sleep drags down mood, low mood disturbs sleep, and stress feeds both. That’s normal, and it’s still useful to know which one seems to be leading.

Could you be short on sleep without realising it?

Yes, and it’s one of the most common reasons for daytime tiredness. Some people simply don’t give themselves enough time in bed. Others spend eight hours there but sleep lightly, wake often or have their sleep disturbed by something they’re not aware of, such as loud snoring or pauses in breathing.

If you’re actually dozing off during the day, the Epworth sleepiness test is a good place to start. Developed by Australian doctor Murray Johns in 1991, the Epworth Sleepiness Scale asks how likely you are to doze off in eight everyday situations, such as sitting and reading, being a passenger in a car for an hour, or sitting quietly after lunch. It’s about actually falling asleep, not just feeling tired. Doctors and sleep clinics use it all over the world.

Each situation scores 0 to 3, for a total from 0 to 24:

• 0 to 5, not sleepy by day: you rarely nod off, so your tiredness is more likely the ordinary kind than a struggle to stay awake.
• 6 to 10, a little sleepy: you get drowsy in quiet moments, as many people do.
• 11 to 12, sleepier than most: you nod off more easily than most people, which is worth mentioning to a doctor.
• 13 to 15, quite sleepy: sleepiness is probably getting in the way of your days and is worth getting checked.
• 16 to 24, very sleepy: try to see a doctor soon, and take extra care on the road.

A higher score doesn’t tell you why you’re sleepy, but it does give you and your doctor something concrete to start from. If a partner has noticed you snoring loudly, gasping or stopping breathing for a moment at night, tell your doctor that too, because it can point to a sleep problem that’s worth investigating. And whatever your score, please don’t drive when you feel drowsy.

What if you can’t sleep even though you’re exhausted?

That combination, tired all day but awake at night, is typical of insomnia. You might take a long time to fall asleep, wake in the night and lie there, or wake too early and not get back off. Often your mind won’t switch off, and the more you try to sleep, the more alert you feel.

The insomnia check uses the Insomnia Severity Index, developed by psychologist Charles Morin. It asks about falling asleep, staying asleep and waking too early over the last two weeks, and how much that’s bothering you and affecting your days. Totals run from 0 to 28: 0 to 7 is few sleep problems, 8 to 14 some sleep trouble, 15 to 21 means sleep is a struggle, and 22 to 28 means sleep is very hard.

Insomnia often starts during a stressful time and then carries on after the stress has passed, kept going by worry about sleep itself and by habits like lying in bed awake for long stretches. The good news is that it’s very treatable. For long-lasting insomnia, the usual first recommendation is a structured talking therapy called cognitive behavioural therapy for insomnia (CBT-I), and a doctor can tell you how to get it. In the meantime, a regular wake-up time, some morning daylight and a wind-down before bed all help. Slow breathing can make the wind-down easier: our post on 4-7-8 breathing for bedtime explains one simple method.

Could low mood be what’s draining your energy?

It might be, especially if the tiredness comes with losing interest in things you usually enjoy. Low energy is one of the most common signs of depression, and for some people it’s the first thing they notice, long before they’d describe themselves as sad.

Signs that mood may be behind your tiredness:

• sleep doesn’t refresh you, however long it is
• small tasks like showering or replying to a message feel like a mountain
• things you used to look forward to feel flat
• you’re harder on yourself than usual
• you find it hard to concentrate or make decisions

Two of the nine questions in the PHQ-9 low mood check ask directly about sleep and about feeling tired or having little energy, and the others ask about mood, interest, appetite, self-worth and concentration. That makes it a good way to see whether your tiredness sits alongside other signs of low mood. Its total runs from 0 to 27, and from 10 upwards it’s worth talking to a doctor. Our post on reading your PHQ-9 result goes through each band, and if you’re wondering whether you’re simply going through a hard patch, telling sadness from depression covers that.

How do stress and burnout wear you out?

Long-running stress keeps your body’s alarm system switched on, and running on alert for weeks or months is tiring in itself. You might get through the week on adrenaline and coffee, then crash at the weekend or as soon as you go on holiday.

When the stress is mainly about work and has gone on for a long time, it can turn into burnout: a deep exhaustion that comes with feeling detached or cynical about work and less effective at it. The signs of burnout overlap with low mood, so it’s worth reading about the difference. Recovery from burnout tends to take longer than a weekend off, and our post on recovering from burnout explains what it really involves.

People who care for others, whether as nurses, therapists, carers or parents of ill children, can feel a particular kind of emotional tiredness from absorbing other people’s distress. That has its own name, and there’s more on it in our post about compassion fatigue.

What physical causes are worth checking?

Ongoing tiredness can have physical causes, and many of them are easy to check and treat. That’s why it’s worth seeing a doctor if you’ve felt tired for more than a few weeks without a clear reason, even if you suspect stress or mood is part of the picture.

A doctor will usually ask about your sleep, mood, diet, alcohol and caffeine, any medicines you take and any other symptoms. They may suggest a blood test. Depending on what you tell them, they might look at things such as your iron levels, thyroid, blood sugar, how you’re recovering from a recent illness, or whether a medicine you take could be adding to the tiredness. Changes like pregnancy, menopause or a new long-term condition can play a part too. None of these is something to guess at from home, and tiredness on its own rarely means anything serious, but a check can rule things out or find something simple to fix.

See a doctor sooner if your tiredness comes with other changes you can’t explain, such as losing weight without trying, breathlessness, or generally feeling unwell.

Which check should you start with?

Pick the one that matches the kind of tiredness you have. You can take more than one, and bringing a few results to your doctor gives them a fuller picture than “I’m tired all the time”.

• If you keep nodding off: start with daytime sleepiness. It takes about two minutes.
• If you can’t get to sleep or stay asleep: start with the insomnia check, also about two minutes.
• If you feel flat and nothing appeals: start with the low mood check, about three minutes.

None of these is a diagnosis. Each one shows how much something has been affecting you recently, and whether it’s worth taking further.

What can you do about tiredness this week?

While you work out the cause, a few small changes help most people, whatever is behind the tiredness:

• Get up at the same time every day, including weekends. A steady wake-up time does more for sleep than a fixed bedtime.
• Get daylight early. Some time outside in the morning, even on a cloudy day, helps set your body clock.
• Watch caffeine and alcohol. Caffeine late in the day can delay sleep, and alcohol tends to make sleep lighter and more broken later in the night.
• Keep naps short and early, if you take them at all, so they don’t eat into the night.
• Move a little. It sounds backwards when you’re exhausted, but gentle activity often leaves people feeling less tired, not more.
• Make room for rest that isn’t a screen. A short walk, a few minutes of slow guided breathing or simply sitting quietly can be more restoring than scrolling.

If you’ve tried these for a couple of weeks and you’re still running on empty, that’s a clear sign it’s time for a doctor’s view rather than more willpower.

Putting it together

Constant tiredness is your body telling you something, and it’s worth listening rather than pushing through. Notice whether you’re sleepy, wired or flat, look at your sleep, mood and stress honestly, and get a doctor’s check if it has lasted more than a few weeks. If you often find yourself dozing off, the daytime sleepiness check is a quick first step, and your result is a useful thing to take along to that appointment.