Fatigue is a condition in which you feel exhausted all the time, even if you are well rested. It is not a normal part of getting older — it is a symptom of something that is wrong. There are many different causes of fatigue, so you should see your doctor to find out why you feel so tired.
What is fatigue?
Fatigue is a very common complaint. It’s a symptom of something, not a disease in itself. It can be caused by physical or psychological conditions, and sometimes by a mixture of the two.
When you are fatigued, you feel exhausted all the time, to the point that it affects your daily living as well as your mental and emotional state. Apart from feeling very tired, you might also lack motivation or have problems with concentration and memory. You might also get very tired after you start an activity.
Fatigue often gets worse gradually. You might not realise how much it is affecting you until you think about all the things you could do previously.
What causes fatigue?
Usually, fatigue is caused by stress and anxiety, depression, a virus, or a sleep problem.
Sometimes fatigue is a symptom of a physical condition such as:
- anaemia — not having enough iron in your blood
- sleep apnoea — a condition that affects your breathing while you sleep
- underactive thyroid — when you have too little of the thyroid hormone thyroxine
- coeliac disease — when you are allergic to gluten
- chronic fatigue syndrome — when you have severe, disabling fatigue that lasts for at least 4 months. You may also have other symptoms such as pain in your joints and muscles. Chronic fatigue syndrome is also called myalgic encephalomyelitis (ME).
- diabetes — when your body can’t metabolise glucose. This common condition also causes thirst, a need to go to the toilet frequently, and weight loss.
- glandular fever — an illness caused by a virus that also gives you a sore throat and swollen glands
- restless legs syndrome — when you have the urge to keep moving your legs at night
- heart disease
- problems with your liver or kidneys
- multiple sclerosis
To find out what is causing your fatigue, your doctor will ask you about any other symptoms and do a full examination. They may also order some blood tests or imaging tests, depending on what they think your condition might be.
Treatment will depend on the condition that is causing your fatigue. Sometimes, after treatment, you will feel better almost straight away. However, it might also take several weeks for your fatigue to lessen.
Making sure you have good quality sleep can help you manage fatigue. Ensure you go to bed at the same time each night and stick to healthy sleep habits.
Eating a healthy diet and doing regular physical activity will also help improve your sleep and lessen fatigue. Eat small, frequent meals throughout the day with plenty of fresh fruit and vegetables; avoid junk food; and try to avoid alcohol and caffeine since these can affect your sleep.
If you have fatigue, talk to your doctor about whether it is safe to drive or carry out your normal work duties.
How to prevent fatigue
Fatigue is a symptom of several conditions so it is hard to prevent. But it’s important to listen to your body and see a doctor so they can find the underlying cause.
When to seek help for fatigue
See your doctor if you have fatigue for more than 2 weeks and it’s not getting better even though you are getting enough rest.
Last reviewed: July 2018