What are the causes of tiredness?
Physical causes of tiredness
Tiredness may be due to a wide range of physical illnesses. Examples include:
- A tendency to be lacking in iron (anaemia).
- An underactive thyroid gland (hypothyroidism).
- Heart failure.
- Chest illnesses (including asthma and chronic obstructive pulmonary disease).
- Addison's disease.
- Bowel problems (for example, coeliac disease).
- Carbon monoxide poisoning.
- Having to get up in the night a lot to pass urine, due to problems such as an overactive bladder or an enlarged prostate gland.
- Breathing problems at night interfering with sleep (obstructive sleep apnoea).
- Vitamin D deficiency.
- Glandular fever.
- Chronic fatigue syndrome.
- Pain from other medical conditions keeping you awake at night.
- Side-effects of some medicines (for example, beta-blockers, medicines to lower cholesterol, some painkillers, some antidepressants).
Most physical causes of tiredness will cause other symptoms. Some causes of tiredness (such as anaemia and hypothyroidism) may not cause any other symptoms apart from tiredness.
Psychological causes of tiredness
Psychological tiredness is much more common than tiredness caused by a physical problem. Both anxiety and depression can make you feel very tired. Eating disorders can make you feel tired, particularly if you are underweight or overweight. Any cause of a sleep problem will also cause tiredness during the day.
Stress is a common cause of tiredness, either because it interferes with sleep, or because of the effect of having a worry on your mind all the time.
Other possible causes include:
- Domestic violence.
Lifestyle causes of tiredness
Tiredness can be caused by lifestyle. We often try to cram too much into our lives and as they become more and more busy we can get tired. Lifestyle causes of tiredness include:
- Drinking too much alcohol.
- Having an unhealthy, unbalanced diet.
- Taking recreational drugs.
- Excessive exercise or total lack of exercise.
- Working night shifts, which may lead to a poor sleep pattern and result in tiredness.
- Big life events such as getting married or moving house.
In many cases no specific cause for tiredness is found.
Further reading and references
Tiredness/fatigue in adults; NICE CKS, February 2015 (UK access only)
Hamilton W, Watson J, Round A; Investigating fatigue in primary care. BMJ. 2010 Aug 24341:c4259. doi: 10.1136/bmj.c4259.
Rosenthal TC, Majeroni BA, Pretorius R, et al; Fatigue: an overview. Am Fam Physician. 2008 Nov 1578(10):1173-9.
Vaucher P, Druais PL, Waldvogel S, et al; Effect of iron supplementation on fatigue in nonanemic menstruating women with low ferritin: a randomized controlled trial. CMAJ. 2012 Aug 7184(11):1247-54. doi: 10.1503/cmaj.110950. Epub 2012 Jul 9.
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Patient Platform Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.