Overview
Depression is a mental health condition that can affect mood, concentration, sleep, appetite, energy, and enjoyment of life. It is different from the normal ups and downs that everyone experiences. Symptoms can interfere with work, school, relationships, and self-care. Depression can be mild, moderate, or severe.
Key Symptoms
Common symptoms include persistent sadness, emptiness, irritability, or loss of interest in activities that used to feel meaningful. Many people also notice changes in sleep, appetite, energy, concentration, or movement. Some feel guilt, hopelessness, or worthlessness. In some cases, depression includes thoughts of death, self-harm, or suicide.
Causes and Risk Factors
Depression does not have one single cause. It is linked to a mix of biological, psychological, and social factors, including family history, major stress, trauma, chronic illness, pain, substance use, and some life events such as loss or isolation. Hormonal changes, certain medicines, and other mental health conditions can also play a role. Sometimes depression develops without one clear trigger.
Who Is Affected
Depression can affect people of any age, gender, culture, or background. It may look different across the lifespan, with children and teens sometimes showing irritability, school problems, or withdrawal rather than obvious sadness. Older adults may report tiredness, sleep problems, memory concerns, or loss of interest. People facing conflict, displacement, poverty, discrimination, or long-term health problems may have higher risk.
Diagnosis and Tests
A healthcare professional diagnoses depression by asking about symptoms, how long they have been present, how they affect daily life, and any history of mental or physical health conditions. They may also ask about sleep, substance use, stress, and safety, including any thoughts of self-harm. There is no single blood test that diagnoses depression, but tests may sometimes be used to look for medical problems that can contribute to similar symptoms.
Treatment Categories
Treatment depends on symptom severity, personal preferences, access to care, and any other health conditions. Common approaches include psychotherapy such as cognitive behavioral therapy or interpersonal therapy, antidepressant medicines, or a combination of both. Supportive care may also involve addressing sleep, substance use, stress, trauma, or social needs. Treatment plans should be guided by a qualified healthcare professional.
Living With It
Recovery can take time, and improvement may happen gradually rather than all at once. Keeping regular follow-up appointments, tracking symptoms, and asking trusted people for support can help many individuals stay engaged in care. It may also help to reduce isolation by maintaining contact with family, friends, peer groups, or community supports when possible. Relapses can happen, so early attention to returning symptoms matters.
Diet and Lifestyle
Daily habits do not replace medical care, but they can support overall mental health. Helpful steps may include regular sleep, physical activity, structured routines, time outdoors, limiting alcohol and recreational drugs, and staying connected with others. Eating regular, balanced meals can support energy and general health. If motivation is low, starting with small, manageable changes may be more realistic.
When to Seek Medical Care
Seek medical care if low mood, loss of interest, or other symptoms last two weeks or longer, keep returning, or interfere with work, school, relationships, or self-care. It is also important to get help if symptoms are getting worse, if alcohol or drug use is increasing, or if there are concerns during pregnancy or after childbirth. A healthcare professional can help assess symptoms and discuss treatment options.
When It May Be an Emergency
Get urgent help right away if someone has thoughts of suicide, has a plan or intent to harm themselves, is talking about wanting to die, or is behaving in a way that suggests immediate danger. Emergency help is also needed if a person cannot care for basic needs, becomes severely agitated, or loses touch with reality. Contact local emergency services or go to the nearest emergency department, and do not leave the person alone if immediate risk seems present.