Most people go through periods of feeling down, but when you're depressed you feel constantly sad for weeks or even months, rather than just a few days.
Depression affects people in different ways and can cause a wide variety of symptoms.
They range from lasting feelings of unhappiness and hopelessness, to losing interest in the things you used to enjoy and feeling very tearful. Many people with depression also have symptoms of anxiety
There can be physical symptoms too, such as feeling constantly tired, sleeping badly, having no appetite or sex drive, and various aches and pains.
The symptoms of depression range from mild to severe. At its mildest, you may simply feel persistently low in spirit, while severe depression can make you feel suicidal, that life is no longer worth living.
Most people experience feelings of stress, anxiety or low mood during difficult times. A low mood may improve after a short period of time, rather than being a sign of depression.
Take the NHS mood self-assessment >