I’ve written elsewhere on this website about depression (eg 1st May 2021 blog), making the point that it’s an illness of our time that has been made worse by the Covid pandemic.  I’ve described different types of depression and looked at how medication and talking therapies may be able to help with the condition.  But it might also be useful to think about some of the biggest causes of depression.


There’s no single cause of depression and, depending on the person, there may psychological or biological factors in play or both.  For some people stressful life events may be the trigger whilst for others the roots may lie in the distant past.  Different causes can often combine – for instance, illness producing a low mood which is then followed by the loss of a loved one which tips the individual into depression.  Similarly, a downward spiral of events may come about such as the ending of a relationship which leads a person to withdraw from other social relationships and that is accompanied by drinking too much or misusing substances.

Childhood experiences

Without question difficult experiences in childhood can predispose to later depression.  Any one of a thousand such experiences can be involved but neglect, abuse (physical, emotional, sexual), an unstable or toxic family environment, the loss of a parent or sibling or other traumatic events could all be implicated in the development of depression.

Neither does what happened in the past have to be dramatic.  People are sometimes puzzled as to why they feel depressed when they didn’t experience major abuse.  Yet lots of smaller adverse experiences can accumulate to have an impact that is equal to or perhaps even bigger than one significant traumatic event.

A family history of depression can make it more likely that someone will develop depression and here is where a complex interplay of biological and psychological components may be at work.

Major life events

Along with childhood and adolescence experiences, stressful life events are also among the biggest causes of depression.  Redundancy, divorce, conflict, bullying, assault, financial worries, illness and serious work problems can all take their toll.   Even potentially good events such as moving house, beginning a new job, getting married or retiring can bring on depression.  It’s how we deal with things that’s important.  A lack of support in a stressful period that is stirring up strong emotions might lead to depression as might, once again, the combination of other big events happening at the same time.  In periods of stress we often need others around us and it may not be helpful to stop seeing people and to try and go it alone.  There’s a strong association between depression and loneliness.


Bereavement is obviously a massive life event.  Grieving and the desolation that can accompany it are natural and healthy responses to the loss of someone close to us.  The stages of grieving have to be gone through in order to come out the other side.  (See my blog on these (30th December 2016)).  And we need to remember that any big loss in life counts as a bereavement, not just the death of a person.

Grief can trigger depression and can co-exist with it but there are differences between the two.  For example, healthy grief tends to lessen with time (perhaps a long time) and often happens in waves.  Depression may be more persistent and entail feelings of worthlessness usually not present in grief.


Poor health can have a role in the development of depression.  That’s particularly true when illness is life-threatening, life-changing or chronic.  Conditions affecting the brain and nervous system (including head injuries) can be particularly linked to depression, as can hormonal problems (especially thyroid issues) and symptoms relating to the menstrual cycle or to the menopause.


There is evidence that some natural bodily changes connected with ageing may increase one’s risk of becoming depressed.  Clearly in old age other factors may also be implicated such as the loss of a partner or other family members, loneliness, lack of social support including friends, failing faculties (eyesight, hearing etc) and no longer being able to participate in enjoyable activities.

Substance misuse

Depression is frequently present in those abusing substances.  People who are depressed may drink or use drugs to improve their mood but a substance such as alcohol is itself a depressant which can increase low mood and tiredness.  Even if substances temporarily make a person feel better they often exacerbate depression in the longer term.

Getting help

The above is intended to be no more than a quick survey of some of the biggest causes of depression.  It might be worth repeating from my May 2021 blog that various treatments are available for the illness.  Medication can make a real difference and can be an alternative or an adjunct to a talking therapy such as CBT (Cognitive Behavioural Therapy) or psychodynamic psychotherapy.