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What Is Depression?

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Depression (major depressive disorder) is a common and serious medical illness that negatively affects how you feel, the way you think and how you act. Fortunately, it is also treatable. Depression causes feelings of sadness and/or a loss of interest in activities you once enjoyed. It can lead to a variety of emotional and physical problems and can decrease your ability to function at work and at home.

Depression symptoms can vary from mild to severe and can include:

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  • Feeling sad or having a depressed mood
  • Loss of interest or pleasure in activities once enjoyed
  • Changes in appetite — weight loss or gain unrelated to dieting
  • Trouble sleeping or sleeping too much
  • Loss of energy or increased fatigue
  • Increase in purposeless physical activity (e.g., inability to sit still, pacing, handwringing) or slowed movements or speech (these actions must be severe enough to be observable by others)
  • Feeling worthless or guilty
  • Difficulty thinking, concentrating or making decisions
  • Thoughts of death or suicide

Symptoms must last at least two weeks and must represent a change in your previous level of functioning for a diagnosis of depression.

Also, medical conditions (e.g., thyroid problems, a brain tumor or vitamin deficiency) can mimic symptoms of depression so it is important to rule out general medical causes.

Depression affects an estimated one in 15 adults (6.7%) in any given year. And one in six people (16.6%) will experience depression at some time in their life. Depression can occur at any time, but on average, first appears during the late teens to mid-20s. Women are more likely than men to experience depression. Some studies show that one-third of women will experience a major depressive episode in their lifetime. There is a high degree of heritability (approximately 40%) when first-degree relatives (parents/children/siblings) have depression.

Depression Is Different From Sadness or Grief/Bereavement

The death of a loved one, loss of a job or the ending of a relationship are difficult experiences for a person to endure. It is normal for feelings of sadness or grief to develop in response to such situations. Those experiencing loss often might describe themselves as being “depressed.”

But being sad is not the same as having depression. The grieving process is natural and unique to each individual and shares some of the same features of depression. Both grief and depression may involve intense sadness and withdrawal from usual activities. They are also different in important ways:

  • In grief, painful feelings come in waves, often intermixed with positive memories of the deceased. In major depression, mood and/or interest (pleasure) are decreased for most of two weeks.
  • In grief, self-esteem is usually maintained. In major depression, feelings of worthlessness and self-loathing are common.
  • In grief, thoughts of death may surface when thinking of or fantasizing about “joining” the deceased loved one. In major depression, thoughts are focused on ending one’s life due to feeling worthless or undeserving of living or being unable to cope with the pain of depression.

Grief and depression can co-exist For some people, the death of a loved one, losing a job or being a victim of a physical assault or a major disaster can lead to depression. When grief and depression co-occur, the grief is more severe and lasts longer than grief without depression.

Distinguishing between grief and depression is important and can assist people in getting the help, support or treatment they need.

Risk Factors for Depression

Depression can affect anyone—even a person who appears to live in relatively ideal circumstances.

Several factors can play a role in depression:

  • Biochemistry: Differences in certain chemicals in the brain may contribute to symptoms of depression.
  • Genetics: Depression can run in families. For example, if one identical twin has depression, the other has a 70 percent chance of having the illness sometime in life.
  • Personality: People with low self-esteem, who are easily overwhelmed by stress, or who are generally pessimistic appear to be more likely to experience depression.
  • Environmental factors: Continuous exposure to violence, neglect, abuse or poverty may make some people more vulnerable to depression.

How Is Depression Treated?

Depression is among the most treatable of mental disorders. Between 80% and 90% percent of people with depression eventually respond well to treatment. Almost all patients gain some relief from their symptoms.

Before a diagnosis or treatment, a health professional should conduct a thorough diagnostic evaluation, including an interview and a physical examination. In some cases, a blood test might be done to make sure the depression is not due to a medical condition like a thyroid problem or a vitamin deficiency (reversing the medical cause would alleviate the depression-like symptoms). The evaluation will identify specific symptoms and explore medical and family histories as well as cultural and environmental factors with the goal of arriving at a diagnosis and planning a course of action.

Brain chemistry may contribute to an individual’s depression and may factor into their treatment. For this reason, antidepressants might be prescribed to help modify one’s brain chemistry. These medications are not sedatives, “uppers” or tranquilizers. They are not habit-forming. Generally antidepressant medications have no stimulating effect on people not experiencing depression.

Antidepressants may produce some improvement within the first week or two of use yet full benefits may not be seen for two to three months. If a patient feels little or no improvement after several weeks, his or her psychiatrist can alter the dose of the medication or add or substitute another antidepressant. In some situations other psychotropic medications may be helpful. It is important to let your doctor know if a medication does not work or if you experience side effects.

Psychiatrists usually recommend that patients continue to take medication for six or more months after the symptoms have improved. Longer-term maintenance treatment may be suggested to decrease the risk of future episodes for certain people at high risk.

Psychotherapy, or “talk therapy,” is sometimes used alone for treatment of mild depression; for moderate to severe depression, psychotherapy is often used along with antidepressant medications. Cognitive behavioral therapy (CBT) has been found to be effective in treating depression. CBT is a form of therapy focused on the problem solving in the present. CBT helps a person to recognize distorted/negative thinking with the goal of changing thoughts and behaviors to respond to challenges in a more positive manner.

Psychotherapy may involve only the individual, but it can include others. For example, family or couples therapy can help address issues within these close relationships. Group therapy brings people with similar illnesses together in a supportive environment, and can assist the participant to learn how others cope in similar situations.

Depending on the severity of the depression, treatment can take a few weeks or much longer. In many cases, significant improvement can be made in 10 to 15 sessions.

ECT is a medical treatment that has been most commonly reserved for patients with severe major depression who have not responded to other treatments. It involves a brief electrical stimulation of the brain while the patient is under anesthesia. A patient typically receives ECT two to three times a week for a total of six to 12 treatments. It is usually managed by a team of trained medical professionals including a psychiatrist, an anesthesiologist and a nurse or physician assistant. ECT has been used since the 1940s, and many years of research have led to major improvements and the recognition of its effectiveness as a mainstream rather than a "last resort" treatment.

Self-help and Coping

There are a number of things people can do to help reduce the symptoms of depression. For many people, regular exercise helps create positive feeling and improves mood. Getting enough quality sleep on a regular basis, eating a healthy diet and avoiding alcohol (a depressant) can also help reduce symptoms of depression.

Depression is a real illness and help is available. With proper diagnosis and treatment, the vast majority of people with depression will overcome it. If you are experiencing symptoms of depression, a first step is to see your family physician or psychiatrist. Talk about your concerns and request a thorough evaluation. This is a start to addressing your mental health needs.

Related Conditions

The six tabs below provide brief descriptions of six conditions related to Depression: Peripartum depression (previously postpartum depression), seasonal depression (also called seasonal affective disorder), bipolar disorders, persistent depressive disorder (previously dysthymia), premenstrual dysphoric disorder, and disruptive mood dysregulation disorder. 

Physician Review

Felix Torres, M.D., MBA, DFAPA

October 2020

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