SummaryRead the full fact sheet
- Fatigue can be caused by a number of factors working in combination, such as medical conditions, unhealthy lifestyle choices, workplace problems and stress.
- Fatigue is a known risk factor in motor vehicle and workplace accidents.
- Always see your doctor for diagnosis if you are suffering from chronic tiredness.
On this page
Fatigue is a feeling of constant tiredness or weakness and can be physical, mental or a combination of both. It can affect anyone, and most adults will experience fatigue at some point in their life.
Each year, around 1.5 million Australians see their doctor about fatigue. Fatigue is a symptom, not a condition. For many people, fatigue is caused by a combination of lifestyle, social, psychological and general wellbeing issues rather than an underlying medical condition.
Although fatigue is sometimes described as tiredness, it is different to just feeling tired or sleepy. Everyone feels tired at some point, but this is usually resolved with a nap or a few nights of good sleep. Someone who is sleepy may also feel temporarily refreshed after exercising.
If you are getting enough sleep, good nutrition and exercising regularly but still find it hard to perform everyday activities, concentrate or be motivated at your normal levels, you may be experiencing fatigue that needs further investigation.
Symptoms of fatigue
Fatigue can cause a vast range of other physical, mental and emotional symptoms including:
- chronic tiredness or sleepiness
- sore or aching muscles
- muscle weakness
- slowed reflexes and responses
- impaired decision-making and judgement
- moodiness, such as irritability
- impaired hand-to-eye coordination
- appetite loss
- reduced immune system function
- blurry vision
- short-term memory problems
- poor concentration
- reduced ability to pay attention to the situation at hand
- low motivation.
Causes of fatigue
The wide range of causes that can trigger fatigue include:
- Medical causes – unrelenting exhaustion may be a sign of an underlying illness, such as a thyroid disorder, heart disease or diabetes.
- Lifestyle-related causes – alcohol or drugs or lack of regular exercise can lead to feelings of fatigue.
- Workplace-related causes – workplace stress can lead to feelings of fatigue
- Emotional concerns and stress – fatigue is a common symptom of mental health problems, such as depression and grief, and may be accompanied by other signs and symptoms, including irritability and lack of motivation.
Fatigue can also be caused by a number of factors working in combination.
Medical causes of fatigue
There are a number of diseases and disorders which trigger fatigue. If you experience prolonged bouts of fatigue, consult your doctor.
Lifestyle-related causes of fatigue
Common lifestyle factors that can cause fatigue include:
- Lack of sleep – typically adults need about eight hours of sleep each night. Some people try to get by on fewer hours of sleep.
- Too much sleep – adults sleeping more than 11 hours per night can lead to excessive daytime sleepiness.
- Alcohol and drugs – alcohol is a depressant drug that slows the nervous system and disturbs normal sleep patterns. Other drugs, such as cigarettes and caffeine, stimulate the nervous system and can cause insomnia.
- Sleep disturbances – disturbed sleep may occur for a number of reasons, for example, noisy neighbours, young children who wake in the night, a snoring partner, or an uncomfortable sleeping environment such as a stuffy bedroom.
- Lack of regular exercise and sedentary behaviour – physical activity is known to improve fitness, health and wellbeing, reduce stress, and boost energy levels. It also helps you sleep.
- Poor diet – low kilojoule diets, low carbohydrate diets or high energy foods that are nutritionally poor don’t provide the body with enough fuel or nutrients to function at its best. Quick fix foods, such as chocolate bars or caffeinated drinks, only offer a temporary energy boost that quickly wears off and worsens fatigue.
- Individual factors – personal illness or injury, illnesses or injuries in the family, too many commitments (for example, working two jobs) or financial problems can cause fatigue.
Workplace-related causes of fatigue
Common workplace issues that can cause fatigue include:
- Shift work – the human body is designed to sleep during the night. This pattern is set by a small part of the brain known as the circadian clock. A shift worker confuses their circadian clock by working when their body is programmed to be asleep.
- Poor workplace practices – can add to a person’s level of fatigue. These may include long work hours, hard physical labour, irregular working hours (such as rotating shifts), a stressful work environment (such as excessive noise or temperature extremes), boredom, working alone with little or no interaction with others, or fixed concentration on a repetitive task.
- Workplace stress – can be caused by a wide range of factors including job dissatisfaction, heavy workload, conflicts with bosses or colleagues, bullying, constant change, or threats to job security.
- Burnout – can be described as striving too hard in one area of life while neglecting everything else. ‘Workaholics’, for example, put all their energies into their career, which puts their family life, social life and personal interests out of balance.
- Unemployment – financial pressures, feelings of failure or guilt, and the emotional exhaustion of prolonged job hunting can lead to stress, anxiety, depression and fatigue.
Psychological causes of fatigue
Studies suggest that psychological factors are present in at least 50 per cent of fatigue cases. These may include:
- Depression – this illness is characterised by severe and prolonged feelings of sadness, dejection and hopelessness. People who are depressed commonly experience chronic fatigue.
- Anxiety and stress – a person who is chronically anxious or stressed keeps their body in overdrive. The constant flooding of adrenaline exhausts the body, and fatigue sets in.
- Grief – losing a loved one causes a wide range of emotions including shock, guilt, depression, despair and loneliness.
As fatigue can present a vast range of symptoms and be caused by many different factors working in combination, diagnosis can be difficult. Your doctor may diagnose fatigue using a number of tests including:
- Medical history – recent events such as childbirth, medication, surgery or bereavement may contribute to fatigue.
- Physical examination – to check for signs of illness or disease. Your doctor may also ask detailed questions about diet, lifestyle and life events.
- Tests – such as blood tests, urine tests, x-rays and other investigations. The idea is to rule out any physical causes, for example anaemia, infection or hormonal problems.
Fatigue is a symptom –something you can feel and describe – not a condition or disease. To reduce your fatigue you first need to understand what the underlying reasons for your fatigue are.
If fatigue is having a negative effect on your quality of life, or causing you distress, then consider speaking with a health professional. By asking questions, they will help you work out why you are experiencing fatigue, and offer some suggestions on how to find relief.
If necessary, your doctor might suggest certain medical tests if there is a reasonable chance the cause of your fatigue may be an undiagnosed medical issue (for example, anaemia or thyroid dysfunction).
Fortunately, for most people fatigue will get better over time on its own or with some simple and practical lifestyle changes.
Where to get help
- Your GP (doctor)
- Wilson J, Morgan S, Magin P, et al., Fatigue – a rational approach to investigation, Australian Family Physician, vol. 43, no. 7, pp. 457-461, The Royal Australian College of General Practitioners.
- Fatigue,, MedlinePlus, US National Library of Medicine.
- Fatigue, Mayo Clinic, USA.
- Fatigue in the workplace, WorkSafe Victoria.
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