Why am I so tired all the time? 16 possible reasons you're feeling exhausted

Time for some lifestyle changes

a woman sat on a bed with hereyes closed and hand on forehead wondering why am I so tired all the time
(Image credit: Future/Getty)

There are a number of reasons why you could be feeling so tired all the time, from too many late nights and early mornings to more serious conditions such as insomnia. 

Feeling tired all the time is no new feat, in fact it's so common that the NHS has already made it into an acronym. TATT stands for "tired all the time" and it's linked to a lack of sleep, among other issues like waking up too early in the morning as well as struggling to wake up.

Tiredness and exhaustion in the long-term doesn't only make it harder to live your life to the full, but can cause health problems in the future. 

Why am I so tired all the time? 16 possible reasons

1. Lack of a balanced diet

If you feel tired after eating and throughout the day, you might be suffering from an unbalanced diet - and did you know there are even some foods that can help you sleep? Make sure your getting your five-a-day and plenty of protein.

Eating foods with high antioxidant levels, also known as superfoods, improve your immune system and prevent you from feeling run down and tired. Common superfoods include fruit and vegetables, dairy products, melons, berries, dark and fibrous vegetables, whole grains and meat.

Feeling tired has also been linked to nutritional deficiencies that come with having an unbalanced diet. According to nutritionist Kim Pearson, “Common deficiencies that can lead to tiredness include iron and vitamin D. Opt for iron-rich foods such as spinach, kidney beans, chickpeas or grass-fed red meat, and take a daily vitamin d supplement. Vegans and vegetarians may lack iron and B12, two key nutrients for energy."

She adds, "“Vegans should take B12 and iron supplements, as well as vitamin D, while fussy eaters should consider a good quality multivitamin and mineral."

A lack of magnesium is another deficiency that could be to blame for a lack of deep sleep. “Low energy levels have been linked to low magnesium levels, as it’s needed to produce adenosine triphosphate (ATP), which is essential for energy,” nutritionist Rick Hay explains. When magnesium levels are low, it’s harder to stay asleep too. So, up your intake of magnesium-rich foods, such as green leafy vegetables, nuts and dark chocolate.

Some people also use magnesium butter which has properties that have been proven to improve sleep quality.

2. Too much exercise during the day

It's normal to feel tired after working out, but fatigue is something different and occurs when you don't fully recover from the exercise. It normally leads to people feeling drained and exhausted, especially during or immediately after exercise.

Doing too much exercise is a natural contributor to this feeling. Try to cut back on the hours spent in the gym or in the swimming pool, make sure you're fully hydrating after working out and restoring essential electrolytes, and be sure to get a good night's sleep after intense physical exercise.

Additionally, fatigue and exhaustion can occur when you don't fuel up and eat before a workout. Without carbohydrates to feed off of during exercise, your body has to use its reserves of protein, fat and carbohydrates for energy - which can lead to you feeling tired.

However, exercise is still important for your general wellbeing. “Fresh air and brisk walks are effective ways to boost your energy, as they get the heart pumping and increase your blood flow,” says GP Dr Roger Henderson. So instead, opt for work outs three to five times a week and be sure to schedule in proper rest days.

3. Heavy periods

If you feel tired before your period starts, you could be suffering from a lack of iron or even anaemia.

The body uses iron to make hemoglobin, which is a protein in red blood cells that carries oxygen from the lungs to other parts of the body. It also helps to make myoglobin, another protein that helps to provide oxygen to the muscles.

A lack of iron means a lack of these two proteins and this makes it harder for oxygen to reach your tissues and muscles. Deprived of energy, the heart has to work harder to move the blood around your body which makes you feel tired.

You can also suffer from anaemia all month long, not just when you're on your period. Try eating foods that have a lot of iron in them like liver, baked beans and curly kale or taking supplements. Talk to your doctor or health provider if you are concerned.

4. Too much sleep

Too much sleep can make you feel tired when you wake up as you're disrupting the body's biological clock. Otherwise known as the circadian pacemaker, this group of cells in the brain controls hunger, thirst, sweat and internal rhythms, including tiredness.

The pacemaker is triggered by light signals from your eye, signalling that it's daylight and the morning. It then sends out chemical messages to the rest of the body to suggest it's time to wake up.

When you have too much sleep, the pacemaker is thrown off it's regular schedule, which can make you feel fatigued as your body began to wake up hours ago.

Indeed a 2018 study by the University of Western Ontario found that those sleeping too much could experience a detrimental effect on their brain.

To help combat this, sleep expert James Wilson (aka The Sleep Geek) recommends including natural light in your morning routine to help you feel more alert in the mornings. He says, "Having natural light earlier in the day helps your body to understand it is now daytime.

"It will reduce your lethargy and improve your alertness. This can be done by getting outside earlier in the day and using a sunshine alarm clock which has a light that rises like the sun and pulls your body out of sleep."

5. Waking up a lot in the night

A lot of us wake up in the night so briefly that we can't remember doing it. It makes us think we've slept right through but in the end, waking up more than five times a night can be the equivalent of losing an hour's sleep. So while there might be plenty of reasons for waking up in the middle of the night, including the symptoms of menopause and insomnia, as well as not knowing what sleeping position is best and therefore possibly increasing levels of pain and discomfort, the there are other more natural reasons like noises in the house or outside.

So if you fit into the latter category, try this simple technique used by registered nutritionist and army veteran, Rob Hobson. Reportedly used by the US military in the past to help people to fall asleep in difficult circumstances: "This technique is said to work for around 96 per cent of people after practising for around six weeks," he says.

How to fall asleep in 2 minutes (via Youtube)

  • Relax the muscles in your face, such as tongue, jaw and around the eyes.
  • Drop shoulders as low as they will go, followed by your upper and lower arm, one side at a time.
  • Breathe out, relaxing your chest then legs, working downwards from the thighs to the feet.
  • Say ‘Don’t think, don’t think’ for 10 seconds to clear your mind.

By setting a proper routine for yourself, it's also possible that your body will adapt better to times when it should be asleep and awake so you'll feel less tired. To do this, it's important to fix your sleep schedule and go to bed at the same time every night, then wake up at the same time every morning.

6. Too hot or too cold in bed

If you're too hot or too cold to get to sleep, this is going to affect the quality of sleep you manage to get overnight.

It's also going to leave you feeling less than refreshed come the morning. “Getting a comfortable night’s sleep can be more challenging during the hottest months” says Thom Hemelryk founder of the Drowsy sleep company.

"Increased temperatures make it harder for us to drift off and mean we toss and turn more than the usual. But then sleeping with the windows open also increases outside light and noises that can keep us up."

Thom says the key to how to sleep in the heat is all about regulating your body temperature, “Your body temperature naturally peaks in the evening and then drops when you are asleep. Even slight changes to your normal patterns can be disruptive. So, it's important to be aware of your temperature patterns and prepare accordingly.”

He suggests these 3 hacks for summer temperature control:

  • Invest in a good fan, it keeps the temperature down and blocks out external noise.
  • Sleep with a light cotton sheet instead of a quilt. If temperatures really soar, try rinsing it in water to keep you cool.
  • Don't sleep naked as this could actually make you hotter.
  • Have your own bedding! In the winter it might be great to cuddle up to your partner to keep warm, but in the summer the heat from your two bodies can make you more uncomfortable. Regulate things by having separate bedding for both of you.

While keeping your bed cool or warm is vitally important for good sleep, it's also a good idea to make sure that you keep your house cool to ensure proper temperature regulation.

7. You need a new pillow or mattress

A new mattress should be purchased every 7-10 years. If your one is starting to reach the end of its life cycle, it could be impacting your sleep.

Before buying a new one, it's important to understand your own preference and the different options available when you shop.

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Cool Gel Foam 2,000 Pocket Sprung Hybrid Mattress

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This mattress is expertly crafted by 'sleep experts' no less/ It has four layers and promises to cool you sleep - great for sweaty sleepers. With cool gel foam on the top and a layer of individually wrapped heat tempered pocket springs in the middle.

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Octasmart Plus Memory Foam Mattress

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Invest in this award-winning mattress it promises to transform sleep. The unique structure makes the mattress breathable, and if the UK are due anymore 40 degree heat waves, breathable is what we need. 

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Emma Premium mattress

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Award-winning, best-selling and breathable three great words to describe your new mattress. With 6 layers for enhanced support and comfort while sleeping, this mattress is ultra breathable and promises no more over-heating, so you may be okay(ish) in the next heatwave. 

Even if you go to bed early and think you're sleeping through until morning, your pillow could be undoing all this good work. The right pillow will support your neck and spine and prevent back pain. An old or uncomfortable pillow means that you'll toss and turn all night which stops your body getting the rest it needs, making you feel tired.

Pillow test: Place the middle of the pillow over your arm, if the sides hang down it's time to buy a new one!

8. Smoking or drinking alcohol before bed

We often feel sleepy after drinking a lot of alcohol, so you're fooled into thinking it aids sleep. But actually, our quality of sleep is affected after having a few drinks and you'll feel tired the next day. Similarly, smoking last thing at night can mean your quality of sleep suffers - even though you think you've had enough sleep. This is because like alcohol, nicotine is a stimulant.

Drowsy's Tom Hemelryk explains, "Stimulants like alcohol, tobacco and heavy foods in the run up to bed will disrupt the chemical balance in your brain needed for restful sleep." Why not try one of the best non-alcoholic wines instead?

If you do smoke, try to have your last cigarette at least four hours before bedtime. Nicotine patches or chewing gum can also affect your sleep. It's also best to avoid drinking large amounts of alcohol close to bedtime if you are feeling tired or having sleep problems.

9. Watching too much TV before bed

Rebecca Small, assistant medical director at Bupa says, "Television, laptop and computer games can all stimulate the mind and therefore can prevent a good night's sleep. Reading, meditation and exercise such as yoga can have a relaxing affect, helping prepare your body for sleep."

Even having the light from street lamps come through your windows can disrupt your sleep, as the high-intensity LED light emits the same blue light as a screen, although it's a smaller quantity. The American Medical Association have even issued a warning about street lights.

"The blue light emitted from phones, laptops and TVs can delay the release of sleep-inducing melatonin by up to three hours,” says Dr Vishal Shah, medical director at Thriva.

To avoid this blue light from screens, try limiting your TV watching and texting to an hour a night, and don't let it be the last thing you do before you go to bed and don't use your bed for anything other than sleeping. It's not a good idea to watch TV in bed, or anything else like sorting out bills, make shopping lists or arguing. Let your body recognise that when you get into bed it's time for sleep.

As for the street lights, make sure to use black-out curtains to ensure that no light creeps through!

10. Spending too much time indoors

If your day is made up of waking up, getting in the car, working in an office or staying at home all day and then going to bed, you probably don't get enough fresh air or sunshine.

Fresh air gives you a burst of oxygen and sunshine gives you vitamin D. Both these elements boost your energy levels and wake you up. They also boost your immune system, so you're less likely to get colds, bugs and other illnesses which make you feel run down.

Getting more sunlight is also how to boost serotonin naturally, due to serotonin’s link to melatonin production, which is the hormone that induces sleep.

"Consistent with previous research, we found individuals who spent less than or around 12 hours outside per week had higher odds of normal sleep compared to those who spent little to no time outside," deemed a 2021 Kentucky-based study.

Try getting out of the office at lunchtime or going for a walk in the evenings. When it's warm enough, open windows and doors too to let the air and sunshine go through your house.

a close up of a black woman running with trees in the background

(Image credit: Getty)

11. Certain medications

There are a lot of tablets and pills that can make you drowsy. Antihistamines, for example.

Many of us don't automatically link the two, even if it says so in the side effects. If you're on medication, this could be making you tired. Or it might be a mixture of tablets which on their own wouldn't affect you but together they might.

Have another look at the leaflets you get with tablets to check and if you're worried have a chat with your doctor, who might be able to suggest a solution.

12. Work and money worries

It's not new to us that worrying about our jobs and our finances makes us feel exhausted. But a 2018 study has confirmed that work and money worries can also cause sleep problems, saying that nearly 1 in 3 of us are having problems sleeping more than once a week. And those who took part in the study said work and money worries were the biggest problems when it comes to nodding off.

Try setting some time aside with your boss or manager to talk through your concerns if you're stressed about work. If you're feeling overworked or not supported, and they should be able to help you. 

Similarly services exist to help you understand and overcome any monetary mental health issues - seek out Mental Health and Money's toolkit if you think it's relevant to you. Even a small step like this will make you feel like you are doing something about it and you'll feel better.

13. Feeling unwell

The most common theory on why you feel tired when you're unwell is that the body is forcing you to slow down. By slowing down and making you feel more tired, and so if you sleep more, the body has the chance to heal and fight off the infection.

14. An underlying health problem

Depression, Seasonal Affective Disorder (SAD) and going through menopause can all make you feel tired, fed up and sluggish as well as disrupt your sleeping pattern.

People who have SAD need a lot of sunshine to boost their mood and energy levels, so much so that many buy light boxes to simulate sunshine during the winter. And if you suffer from depression or are struggling with the symptoms of the menopause there are natural ways you can boost your energy levels which will make you feel happier, more awake and help you cope with all that the menopause might throw at you!

There are other health problems which can make you tired too. These include Restless Leg Syndrome, hypothyroidism, diabetes, high and low blood pressure and Irritable Bowel Syndrome. Talk to your doctor or health provider if you are concerned.

“If you’re feeling tired for longer than a couple of weeks, see your GP,” says Dr Shah.

“As soon as you notice any change in your appetite, you feel pain, notice blood in your stools or urine, or are worried about any other symptoms, go and see your doctor.”

15. Not drinking enough water

Being dehydrated is one of the most common reasons for feeling tired all the time as your body is trying to work without enough water. This can cause periods of exhaustion, fatigue and low energy - as well as general tiredness.

The average recommended water intake is around three litres per day.

16. Too much tea or coffee

Caffeine is a quick pick-me-up, but it can stay in your body for five to six hours. “This means any consumption in the afternoon and evenings will still affect your brain when you’re trying to sleep at night,” says Dr Alison Bentley.

Ideally, you want to have your last cup at 3pm. But if you can’t, swap to green tea. “Green tea has caffeine but also l-theanine, which mutes the excess stimulating effect of caffeine,” says nutritionist Dana James

She also recommends avoiding non-organic drinks (ie teabags treated with pesticides, genetically modified organisms or synthetic fertilisers) to beat the afternoon slump. “Pesticide residue ends up in your coffee and that makes you feel tired,” she says.

a profile picture of James Wilson
James Wilson

James Wilson, AKA The Sleep Geek is a Sleep Behaviour and Environment Expert. He has successfully helped professional athletes, among others, to understand their sleep better and improve their sleep behaviours.

a profile picture of Thomas Hemelryk
Thomas Hemelryk

Founder and creative director of Drowsy Sleep Co. A cult UK beauty brand showcasing "The world's most luxurious sleep mask" and multiple award-winning, luxury sleep aids.

a profile picture of Dr Vishal Shah
Dr Vishal Shah

Dr. Vishal Shah is Medical Director at Thriva, and a GP with 15 years of experience working in the NHS. He has a special interest in lifestyle medicine and digital health. He is passionate about the role of technology to empower patients and creating innovative solutions to healthcare problems.

Lucy Gornall
Health & Fitness writer

Freelance writer Lucy Gornall is the former health and fitness editor for various women’s magazines including Woman&Home Feel Good You. She has previously written for titles including Now, Look and Cosmopolitan, Woman, Woman's Own, Woman's Weekly and Chat. She lives and breathes all things fitness.

With contributions from