Depression Disorder: Causes and Symptoms

Author : Ojas Neuropsychiatry Center | Published On : 14 Jul 2026

Depression, also known as Major Depressive Disorder (MDD), is a mood disorder characterized by persistent sadness, loss of interest in activities, and emotional as well as physical symptoms that last for at least two weeks or longer.

Depression is a medical condition—not a personal weakness or lack of willpower. It can affect people of all ages and backgrounds.

Common Symptoms of Depression

Symptoms may vary from person to person but often include:

• Persistent sadness or low mood
• Loss of interest or pleasure in previously enjoyable activities
• Fatigue or lack of energy
• Difficulty concentrating or making decisions
• Changes in appetite or weight
• Sleeping too much or difficulty sleeping
• Feelings of hopelessness, guilt, or worthlessness
• Irritability or frustration
• Reduced motivation
• Social withdrawal

Causes of Depression

Depression usually develops due to a combination of biological, psychological, and environmental factors.

Biological Factors

• Brain chemical imbalances
• Hormonal changes
• Family history of depression

Psychological Factors

• Low self-esteem
• Chronic stress
• Anxiety disorders
• Traumatic experiences