Everyone feels sad from time to time. But depression is far more than that — it is a clinical condition that can last for weeks, months or even years, profoundly affecting daily life.
Sadness is usually a temporary emotion triggered by a specific event — a loss, disappointment or failure. It eases with time and support, and the person retains some enjoyment of life.
Depression is different: the low mood does not lift, it persists without a clear cause or out of proportion to circumstances, and the person can no longer enjoy things they once found pleasurable. This disrupts everyday functioning.
DSM-5 diagnostic criterion: the two-week rule
A diagnosis of Major Depressive Disorder requires that at least five of the symptoms listed below are present nearly every day for an uninterrupted period of two weeks. One of those symptoms must be either depressed mood or loss of interest or pleasure.
Emotional
Cognitive
Physical
The most widely recognised type. Symptoms last at least two weeks and significantly impair daily functioning. Episodes may recur.
A milder but chronic form of depression lasting at least two years. The feeling of "I've always been this way" is common.
Begins in autumn–winter and resolves in spring. More prevalent in northern countries and regions with limited sunlight.
Develops after childbirth and is far more severe and prolonged than the "baby blues". It affects approximately 10–15% of mothers.
Global scale
According to the World Health Organisation, approximately 280 million people worldwide are living with depression, making it one of the most prevalent mental health conditions globally. (WHO, 2023)
Depression cannot be attributed to a single cause. It is understood within a biopsychosocial model:
Biological
Psychological
Social
Depression is a condition that can largely be overcome with the right support. The main evidence-based approaches include:
Cognitive Behavioural Therapy (CBT)
Focuses on identifying and changing the negative thought patterns that fuel depression. CBT has the broadest research base of any therapy approach for treating depression.
Antidepressant Medication
Prescribed following psychiatric evaluation. For moderate to severe depression, combining medication with therapy generally yields the best outcomes.
EMDR and Trauma-Focused Therapy
Addresses underlying traumatic experiences to support long-term recovery from depression.
Lifestyle Changes
Regular exercise, sleep hygiene and social connection are important factors that support the treatment process.
If you are having thoughts of harming yourself or others
Please contact a healthcare provider or someone you trust immediately. These thoughts are a symptom of depression and can improve with help.
Mild depression may lift over time; however, moderate to severe depression rarely resolves without professional support and can become chronic. If symptoms persist longer than two weeks, speaking with a psychologist or psychiatrist is recommended.
Sadness is a temporary emotion linked to a specific event. Depression is a clinical condition characterised by persistent low mood, loss of energy, sleep disturbances, and impaired daily functioning—often with no clear trigger—lasting at least two weeks.
Not necessarily. For mild to moderate depression, psychotherapy—especially CBT—can be highly effective on its own. Medication is typically considered for moderate to severe cases and is always assessed on an individual basis.
It varies. Focused CBT for depression commonly runs 8–16 sessions. More complex or long-standing cases may take longer. Your therapist will regularly review progress with you and adjust the plan accordingly.