There is no single cause of depression. It can occur for a variety of reasons and has many different triggers. Understanding the risk factors and contributing factors is important for identifying why depression occurs. For some people, a disruptive or stressful life event, such as grief, divorce, illness, dismissal, work or financial concerns, or major life changes, may be the cause. Often, different causes can be combined to trigger depression.
Depression is caused by an imbalance of brain chemicals. Other factors also play a role, including psychological factors and personality traits, which can influence the likelihood of developing depression. It also tends to run in families, and a family history of depression or other psychiatric or medical conditions is a significant risk factor.
Chronic illness, chronic pain, and physical illness can increase the risk of depression, as ongoing health problems may contribute to feelings of sadness and isolation. Depression is a complex mental illness with biological, psychological, and social aspects. No single factor causes depression; rather, it results from a combination of contributing factors. Certain risk factors, such as family history, chronic illness, and major life changes, can increase depression risk and make some individuals more likely to develop depression.
Major Depressive Disorder
It can also develop without a clear trigger. It is often said that depression is the result of a chemical imbalance, but that way of speaking does not capture the complexity of the disease. Research suggests that depression doesn’t just come from having too much or too little of certain chemicals in the brain. Rather, there are many possible causes of depression, including faulty mood regulation by the brain, genetic vulnerability, and stressful life events. Most psychiatric disorders, including depression, share complex etiologies involving genetic, biological, and environmental factors.
A number of these forces are thought to interact to cause depression. An important development that is being investigated psychopharmacologically for treatment-resistant depression is ketamine, which is used in medicine as an anesthetic. When a person experiences intense and persistent feelings of sadness for long periods of time, they may have a mood disorder, such as major depressive disorder (MDD). Also called major depressive disorder or clinical depression, it affects how you feel, think and behave, and can lead to a variety of emotional and physical problems. Neurobiological research has shown that specific brain regions, such as the hippocampus and prefrontal cortex, are involved in depression, and brain imaging studies are used to identify structural and functional changes associated with depressive disorders.
Depression is classified within the broader categories of depressive disorders and mood disorders, which are types of mental disorders and psychiatric disorders. The four most common types of depression are major depression, persistent depressive disorder, bipolar disorder, and seasonal affective disorder. Other diagnostic categories include single episode depressive disorder and recurrent depressive disorder, which refer to the number and pattern of depressive episodes experienced. Any treatment for depression should coincide with maintaining a healthy diet, regular exercise, a productive sleep schedule, and, yes, even conscious self-care practices. Dysthymia (persistent depressive disorder) and depression (major depressive disorder) are very similar. Depression is diagnosed primarily by history and clinical presentations, or a specific pattern of symptoms, says Dr.
A diagnosis of major depressive disorder (clinical depression) means that you have been feeling sad, depressed, or worthless most days for at least two weeks and that you also have other symptoms such as trouble sleeping, loss of interest in activities, or change in appetite. Depressive symptoms and depression symptoms can include low self esteem, fatigue, difficulty concentrating, and changes in weight or appetite. Your doctor or mental health professional can diagnose major depressive disorder based on your symptoms, feelings, and behaviors. It is important to differentiate depression from other conditions such as anxiety disorders, panic disorder, substance use disorders, eating disorders, and thyroid disorders, as these can present with overlapping symptoms. People with major depression have symptoms of depression most of the day, almost every day, for episodes of at least two weeks and may experience recurrent episodes throughout their lives. A major depressive episode is defined as a period of at least two weeks with pervasive depressive symptoms, and depressive episodes can be single or recurrent, as seen in single episode depressive disorder and recurrent depressive disorder. It is also important to note that when a patient mentions suicidal thoughts, that is an important warning sign.
Depression or major depressive disorder (MDD), the term for clinical depression, is one of the most common mental health conditions, affecting some 350 million people of all age groups. The clinical definition, based on the fifth edition of the Diagnostic and Statistical Manual of Mental Health Disorders (DSM), is “a period of at least two weeks in which a person experienced a depressed mood or loss of interest or pleasure in daily activities, and had most of the specified symptoms, such as such as problems with sleep, diet, energy, concentration or self-esteem. Women have a higher prevalence of suffering a depressive episode than men (8.7% compared to 5.3% of adult men). Major depression is the classic type of depression and what is diagnosed or labeled as MDD (also known as unipolar depression). Severity can range from mild depression, which may respond well to psychosocial interventions, to moderate depression, and up to severe depression or severe major depression, which may require more intensive treatments. Severe cases may include psychotic symptoms such as delusions or hallucinations, and specific types like postpartum depression can occur after childbirth.
Initial treatment for depression is guided by the severity of symptoms, co-existing conditions, and patient preferences, and may involve psychotherapy, antidepressant medications, or a combination. Oral antidepressant medications, including selective serotonin reuptake inhibitors and atypical antidepressants, are commonly prescribed. Electroconvulsive therapy is considered for severe or treatment-resistant cases. Evidence-based psychotherapies such as interpersonal therapy are also effective options. Treating depression often involves a combination of therapies, and strategies to prevent depression, such as early intervention and lifestyle modifications, are important.
If you or someone you know is experiencing depression symptoms, it is important to seek treatment. Early diagnosis and intervention can improve outcomes, and healthcare professionals use clinical evaluation and standardized tools to diagnose depression accurately.
Depression Diagnosed
When depression is diagnosed, it represents a revolutionary breakthrough—qualified mental health authorities have identified the presence of major depressive disorder through a cutting-edge, evidence-based evaluation framework that transforms understanding of your symptoms, medical history, and comprehensive mental health profile. Major depressive disorder is a sophisticated mood condition that transcends occasional feelings of sadness—it is a clinically credible medical condition that can significantly revolutionize daily life, relationships, and physical health outcomes. According to the American Psychiatric Association, depression diagnosed as a depressive disorder requires the exclusive application of proven assessment criteria such as persistent low mood, loss of interest in activities, and changes in sleep or appetite that demonstrate measurable patterns lasting at least two weeks.
Securing a depression diagnosis is a groundbreaking step toward transformative recovery outcomes. A qualified mental health professional will leverage industry-leading, evidence-based criteria to determine if you are experiencing a depressive disorder—ensuring you receive the most innovative support and treatment solutions available. Recognizing depression as a legitimate medical condition revolutionizes stigma reduction and empowers individuals to access cutting-edge intervention strategies early. If you or someone you know is experiencing symptoms of depression, partnering with an authorized mental health specialist can deliver significant, measurable improvements in managing this mood disorder while enhancing overall well-being through proven, results-driven therapeutic frameworks.
