Why am I always tired? Five possible causes of fatigue

Feeling tired is fairly common and can be caused by lots of different things, such as working too much, staying up too late or not being able to fall asleep easily.

So many people report feelings of fatigue that there’s an acronym for it: TATT, which stands for ‘tired all the time’. This specifically refers to a continued feeling of exhaustion and is a common reason for people to visit their GP. 

So what can cause you to feel tired all the time and what can you do to improve your energy levels?

Why am I always tired?

Before you see your GP, think about what could be making you feel tired. Many causes of fatigue can be dealt with by making simple lifestyle changes.

Here are five common reasons why you may be feeling tired all the time.

1. A busy lifestyle

A busy lifestyle is the most common reason for fatigue. Between work, your social life, family and everything else you cram into your day, you can be left with very little energy and no time to unwind. 

Modern lifestyles are very busy, which isn’t helped by our almost constant use of mobile devices and hours spent on social media. This all makes unwinding even harder. 

Looking at how you can improve your work-life balance can help you feel less tired and also reduce your stress levels. Consider: 

  • Cutting down your working hours, if possible
  • Creating a designated workspace if you work from home so you can more easily stick to set work hours rather than working at every opportunity
  • Giving yourself time every day to relax, even if it’s just 20 or 30 minutes at the end of the day
  • Reducing social outings to a couple of times a week
  • Removing or reducing any obvious causes of stress
  • Saying no to things if you’re too tired

2. A poor diet

An unbalanced diet can contribute to feelings of fatigue as you aren’t giving your body the energy and nutrients it needs.

Eating too many refined carbohydrates, such as white bread, white pasta, white rice and sweet desserts, can leave you feeling more tired. This is because they cause a large spike in your blood sugar levels, followed by an equally large drop as your body returns your blood sugar levels back down to normal — this can make you feel tired.

Rather than filling your diet with refined carbohydrates, make sure you’re getting enough fruit, vegetables, nuts and seeds. These are all great sources of fibre, which help maintain your energy levels throughout the day.

You should also make sure you’re getting enough nutrients from your diet to help with your energy levels. Iron and vitamin D deficiencies, specifically, can cause fatigue. Eating iron-rich foods, such as spinach, chickpeas and kidney beans, can help, as can taking vitamin supplements, especially in the winter months when you won’t be getting as much vitamin D from exposure to sunlight.

It’s also important to eat enough calories every day as not eating enough can leave you struggling for energy. The recommended calorie intake for women is 2,000 calories and for men is 2,500 calories.

3. Lots of stress

High levels of stress can cause feelings of fatigue. Worrying about work, family and your finances can make it hard to switch off and get a good night’s sleep

Looking at how you can reduce your stress will help with your mental health, while also improving your sleep pattern. Both will affect how tired you feel. 

You should talk to your employer about work stress, get financial help or create a realistic budget to alleviate money worries, and talk to family and friends about what is causing you stress. It’s also a good idea to ensure you are regularly de-stressing in a way that works for you, whether that’s going for a walk, meditating, reading a book or taking a bath. 

4. Exercising too much

While exercising is good for your physical and mental health, too much exercise can be detrimental. Feeling a bit tired after exercising is normal, but feeling fatigued isn’t and is often a result of your body not being able to recover from exercise.

Your body needs recovery time after every workout to allow it to repair any damage. This means having a rest, drinking enough water and restoring lost electrolytes.

It’s also important to make sure you are eating enough before exercising, otherwise, your body will take energy from its stores of protein, fat and carbohydrates. This can increase the feeling of fatigue after working out.

Rather than exercising every day, aim to work out three to five days a week with rest days in between.

5. Too much sleep

You might think more sleep is always good for you, but this isn’t the case. Sleeping too much can disrupt your body clock, which is also called your circadian pacemaker. This is a group of cells in your brain that control internal rhythms, including how tired you feel.

Light signals from your eyes are sent to these cells, which tells them that it’s daylight. This triggers them to send signals to your body to wake it up. Sleeping too much disrupts these signals and affects your body’s schedule. You ultimately end up feeling tired because you have slept too much and your body started the process of trying to wake you up hours ago.

Sticking to a sleep schedule can help you avoid exhaustion as a result of too much sleep and ensure your body maintains its circadian rhythm.

When should I see my GP about fatigue?

If you can’t identify the cause of your fatigue or you have made lifestyle changes but are still feeling tired all the time, make an appointment with your GP. 

They’ll ask about your lifestyle and your mood to determine if there is something that could be affecting your energy levels, such as anxiety or depression

They may recommend getting tested for some of the most common conditions that can cause fatigue. Tests could include blood tests to check for a vitamin B12 deficiency, anaemia, an underactive thyroid and other conditions. 

If your GP thinks there could be a serious underlying cause, they may refer you to a specialist doctor for further assessment. 

We hope you've found this article useful, however, it cannot be a substitute for a consultation with a specialist

If you're concerned about symptoms you're experiencing or require further information on the subject, talk to a GP or see an expert consultant at your local Spire hospital.

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Author Information

Cahoot Care Marketing

Niched in the care sector, Cahoot Care Marketing offers a full range of marketing services for care businesses including: SEO, social media, websites and video marketing, specialising in copywriting and content marketing.

Over the last five years Cahoot Care Marketing has built an experienced team of writers and editors, with broad and deep expertise on a range of care topics. They provide a responsive, efficient and comprehensive service, ensuring content is on brand and in line with relevant medical guidelines.

Their writers and editors include care sector workers, healthcare copywriting specialists and NHS trainers, who thoroughly research all topics using reputable sources including the NHS, NICE, relevant Royal Colleges and medical associations.


The Spire Content Hub project was managed by:

Lux Fatimathas, Editor and Project Manager

Lux has a BSc(Hons) in Neuroscience from UCL, a PhD in Cellular and Molecular Biology from the UCL Institute of Ophthalmology and experience as a postdoctoral researcher in developmental biology. She has a clear and extensive understanding of the biological and medical sciences. Having worked in scientific publishing for BioMed Central and as a writer for the UK’s Medical Research Council and the National University of Singapore, she is able to clearly communicate complex concepts.

Catriona Shaw, Lead Editor

Catriona has an English degree from the University of Southampton and more than 12 years’ experience copy editing across a range of complex topics. She works with a diverse team of writers to create clear and compelling copy to educate and inform.

Alfie Jones, Director — Cahoot Care Marketing

Alfie has a creative writing degree from UCF and initially worked as a carer before supporting his family’s care training business with copywriting and general marketing. He has worked in content marketing and the care sector for over 10 years and overseen a diverse range of care content projects, building a strong team of specialist writers and marketing creatives after founding Cahoot in 2016.