Tiredness and fatigue

Key points about tiredness & fatigue

  • Fatigue is the feeling of being tired all the time, even after you have rested.
  • Most of the time fatigue is your body’s way of saying you need to make some lifestyle changes. However, sometimes it can be a sign of an underlying condition.
  • Fatigue is common. Women tend to feel more tired than men.
  • If you are getting enough sleep, exercise and healthy food, and generally have a healthy, low-stress lifestyle and are still experiencing fatigue, talk to your doctor.
Tired woman at gym
Print this page

Fatigue is the feeling of being tired all the time. It is different from the feeling of sleepiness you get at bedtime or tiredness after exercise or a late night. Fatigue may be physical (in your body) or psychological (in your mind). 

You are more likely to experience fatigue if you have a physical or mental illness or are on a low-income. Women are more commonly affected than men. 

Fatigue can cause a wide range of symptoms.

  • Physical: feeling tired all the time, headaches, lightheadedness, sore, aching or weak muscles, loss of appetite, prone to getting sick.
  • Mental: slowed reflexes and responses, poor decision making and judgement, short-term memory problems, poor concentration.
  • Emotional: moodiness, irritability, low motivation, feeling depressed and hopeless.

Most of the time fatigue is not due to one thing, but a combination of psychological, physical and lifestyle factors. 


Psychological causes of fatigue are much more common than physical ones.  

It’s common to feel fatigued if you are experiencing:

  • Anxiety– for example, worrying about something so much that it keeps you up at night.
  • Grief or emotional shock – for example, after the death of a loved one or a natural disaster. 
  • Stress – including stress at work, juggling work and family commitments, low income, or even positive events, such as planning a wedding.
  • Depression – fatigue is a common symptom of depression. 


It is common to feel tired when you are:

  • underweight, overweight or obese
  • pregnant or breastfeeding
  • sick or have a health condition such as anaemia, thyroid problems, coeliac disease or diabetes.
  • having cancer treatment such as chemotherapy or radiotherapy
  • taking certain medications – some medications and some combinations of medications can make you feel tired. The tiredness may improve as your body gets used to the new medication or new combination of medications. If you think your medication is causing fatigue, talk to your doctor. They may reduce or change your medication.  


Fatigue can also be caused by lifestyle factors.

  • Drinking too much alcohol: Drinking alcohol in the evening tends to make you wake up in the middle of the night. Drinking too much on a regular basis can affect your mood and your sleep.
  • Having a disturbed sleep pattern: Going to sleep at the same time every night and waking up at the same time every morning helps set your body's natural sleep-wake cycle.
  • Shift work, looking after small children or even just sleeping in on the weekend, can throw your normal sleep pattern off balance. This means your body wants to be sleeping at times when you need to be awake.
  • Drinking too much caffeine: Caffeine is a stimulant that can stress the nervous system and cause insomnia.
  • Not exercising regularlyKeeping active every day is one of the best things you can do to reduce stress and anxiety, help you sleep better and improve your sense of well-being. It seems counter-intuitive, but tiring yourself out with exercise means you’re less likely to feel fatigued.
  • Poor diet: Foods high in sugar provide a short-term energy boost that quickly wears off, making you feel more tired.  A healthy, balanced diet provides your body with the energy and nutrients it needs to function at its best. 

Tiredness + other symptoms

See your doctor if you have fatigue plus any of the following symptoms:

These may be signs of an underlying medical problem. 

Tiredness as the main symptom

If tiredness is your main symptom, and you are getting enough exercise and sleep, eating a balanced diet and have a low-stress lifestyle and are still experiencing fatigue, see your doctor for a check-up. See also our separate page on chronic fatigue syndrome.

Questions a healthcare provider may ask include the following:

  • Do you feel drowsy or weak?
  • Do you feel down or depressed?
  • Has your fatigue developed slowly or suddenly?
  • Is it cyclical or constant?
  • What do you think the cause might be?
  • Have you experienced any significant life events recently?
  • Is your life in balance? Consider work, relationships, physical, emotional, social, sense of worth and recreation.

Your healthcare provider may also:

  • take your sleep history, including how much sleep you get each night, what the quality of your sleep is like, and whether you snore, wake or stop breathing in the night
  • do a physical examination to check for signs of illness or disease
  • carry out tests to rule out physical causes, such as blood and urine tests. 

If you have a medical condition causing fatigue, treatment will focus on the condition. If there is no medical cause, treatment will focus on lifestyle factors. 

Talking therapy (counselling) may be useful if you:

  • are worried or anxious
  • have experienced a major life event
  • are feeling low or depressed.

Improving your diet, getting more exercise, losing or gaining weight if needed, getting a good night’s sleep, cutting down on caffeine and alcohol and avoiding recreational drugs, and drinking enough water can all reduce fatigue and boost your energy. 

Improve your diet

  • Eat a balanced range of vegetables, fruit, whole grains, lean protein and healthy fats.
  • Small, well-balanced meals can help regulate your blood-sugar levels and prevent energy slumps.

Increase your exercise

  • Feeling tired at your desk? A short 15-minute walk can give you an energy boost.
  • Be active every day. Aim to exercise for 2 ½ hours per week.
  • If you feel too tired to exercise, start small and build up slowly.
  • Being active makes you less fatigued, not more and helps you regain your energy and zest for life
  • Ask your GP about a Green Prescription if you need help getting active.
  • Learn more about the benefits of physical activity

Lose weight, gain energy

  • It takes a lot of energy to carry extra weight around.
  • Aim to keep your weight within the healthy range for your height and you’ll feel much more energetic.
  • Learn more about weight loss.

Gain weight, gain energy

  • If you are underweight, your muscles may not be strong enough to support your body.
  • You may also use more energy keeping warm.
  • Learn our weight gain tips

Get a good night's sleep 

  • Go to bed at the same time and wake up at the same time even on the weekends so that you are in sync with your body's natural sleep/wake cycle.
  • Avoid caffeine and alcohol before bed.
  • Keep your bedroom dark, cool and quiet; a place for rest only.
  • Read more sleep tips

Manage stress

  • Stress can be exhausting. Sometimes just acknowledging that something is stressing you out can make you feel better.
  • Try to do something you find relaxing every day, whether it be going for a walk, reading a novel, meditating, listening to music or having a bath.
  • Set aside some time just for yourself.
  • Read more about stress and how to manage it, including at work.

Cut out caffeine 

  • Gradually cut down on caffeine over a 3-week period.
  • Stay off caffeine for a month to see if you feel less tired without it.
  • Learn more about the effects of caffeine.

Cut down on alcohol 

  • Having a few drinks before bed may help go to sleep, but it makes you sleep less deeply and be more likely to wake in the night.
  • Even if you sleep for 8 hours, you’ll still feel tired in the morning.
  • Alcohol also depresses your mood. Read more about alcohol, including alcohol and mental health, and alcohol and harmful drinking.

Avoid drugs

  • Using recreational drugs can make you fatigued as well as creating other long-term problems.
  • Learn more about addiction.

Drink water 

  • Being dehydrated can make you feel tired.
  • Drink water when you feel thirsty.
  • Learn more about the benefits of water.

The following is from Fatigue and TATT(external link) Patient Info Professional, UK, 2019 

Take a systematic approach, focusing on physical, psychological and social issues and lifestyle factors. Only a minority of patients presenting with fatigue will have a serious underlying physical cause. Red flags include:

Differential diagnoses


  • depression
  • obesity
  • obstructive sleep apnoea
  • poor sleep pattern, hard work, stress
  • treatment with a sedative, caffeine withdrawal
  • chronic fatigue syndrome
  • any physical illness may be associated with fatigue, particularly anaemia, iron deficiency, cancer, renal disease, liver disease, heart failure, thyroid disease, diabetes, autoimmune disease.

Other resources

The laboratory investigation of tiredness (external link) BPAC, NZ

There is evidence that iron supplementation improves fatigue scores, particularly among women with baseline fatigue. See 
Daily iron supplementation for improving anaemia, iron status and health in menstruating women(external link) Cochrane Developmental, Psychosocial and Learning Problems Group, 2016


healthy sleep hygiene

Healthy sleep hygiene

Auckland DHB, NZ

are there medical tests for fatigue

Are there medical tests for fatigue?

Choosing Wisely, NZ, 2016

Need help now?

Healthline supporters block

Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Dr Sharon Leitch, GP and Senior Lecturer, University of Otago

Last reviewed:

Page last updated: