What is depression?

Depression is a depressive disorder that involves a person's body, mood, and thoughts. It can affect and disrupt eating, sleeping, or thinking patterns, and is not the same as being unhappy or in a "blue" mood, nor is it a sign of personal weakness or a condition that can be willed or wished away. People with a depressive illness cannot merely "pull themselves together" and get better. Treatment is often necessary and many times crucial to recovery.

There are three primary types of depression: major depression (clinical depression), manic depression (bipolar disorder), and dysthymia (dysthymic disorder).

If you struggle with depression, chances are that you suffer from any or all of the following:

  • difficulty getting out of bed in the morning
  • insufficient energy to function
  • profound sadness
  • self-isolating tendencies
  • lack of motivation
  • loss of appetite
  • suffocating feelings of doom and gloom
  • suicidal thoughts

Your life may in turn be adversely impacted by a profound struggle to care of yourself—including the basics of eating, bathing and grooming, as well as working, socializing and engaging in physical activity. You may end up feeling extreme loneliness, isolation and hopelessness, to the extent that it is a challenge to even think about reaching out for help. Each of these challenges are likely to feed into each other, exacerbating your struggles. 

Depression is an illness. It's not just being sad. When you're depressed, your brain is not working like it should. Depression causes symptoms in your body too. It causes more problems with daily life than any other illness in the U.S.

Anyone can have depression. This includes men and women, rich and poor, young and old. Even children can be depressed.

Depression can make it hard for you to be a good friend, spouse, or parent. It can hurt you at work or school. It can even make you want to hurt yourself. Just like any other medical illness, depression can be treated. With treatment, most people can recover.

Depression affects people in different ways. It can be mild or severe. You may have it only once in your life. It may happen after a stressful event, like the loss of a family member. But many people have it again and again.

Dr. John Preston, PsyD
Psychology Specialist

Serious depression comes in two varieties: unipolar and bipolar. When you have bipolar disorder, you experience both depression and episodes of mania (extreme states of agitation, hyperactivity, euphoria, marked irritability, decreased need for sleep, racing thoughts, and sometimes psychotic symptoms) or hypomania (milder episodes of increased energy, euphoric mood, and decreased need for sleep). Unipolar depression involves only depressive episodes, never mania or hypomania.

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Clinical depression involves intense feelings of sadness, an inability to enjoy pleasurable situations, difficulties with attention and concentration, and multiple physical symptoms such as abnormal sleep, fatigue, and abnormal appetite. Depression is different from normal feelings of sadness. The symptoms of clinical depression interfere with everyday life and function for several weeks or longer. In the U.S., between 10 and 15 percent of the population has suffered from major depression—the most severe form of clinical depression—at some point in their lives. Untreated depression is associated with an inability to function in daily life and an increased risk of suicide.

Depression manifests differently in each individual and varies in its severity and symptoms. Types of depressive illnesses include major depression, bipolar disorder, chronic depression, and Seasonal Affective Disorder (SAD).

Conditions which are most commonly diagnosed are chronic depression and major depressive disorder. Major depressive disorder or clinical depression and chronic depression, is also known as dysthymia or dysthymic disorder.

Depression is more than just feeling "blue" or "down in the dumps" for a few days. It's a serious illness that involves the brain. With depression, sad, anxious, or "empty" feelings don't go away and interfere with day-to-day life and routines. These feelings can be mild to severe. The good news is that most people with depression get better with treatment.

This information is based on source information from the National Women's Health Information Center.

There are all different kinds and nuances of depression, but they can all be serious just the same. There's postpartumdepression, which 10 to 15 percent of recent mothers experience. There's seasonal affective disorder, which is brought on by lack of exposure to sunlight—most notably in northern climates during the winter (although some people actually have the reverse pattern—a summer depression with improvement in the winter). There's also depression brought on by medications, ranging from steroids to narcotics to alcohol to sleeping pills, which suppress dopamine and serotonin, mimicking the chemical reactions that cause depression.

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Depression is a medical illness which presents with a persistent sad mood, loss of pleasure, hopelessness, increased feelings of guilt, preoccupation with death, anxiety, irritability, crying spells, loss of appetite, and changes in sleep pattern. It is a profound sadness or black mood that a person cannot "shake off." Nobody chooses to feel this way and it has nothing to do with one's personality or life circumstances. Depression is a flaw in brain chemistry not character. It occurs as an abnormality in the normal balance of neurotransmitters or messenger molecules. Messenger molecules help communicate between nerve cells and help us think, feel, and concentrate. Serotonin, norepinephrine, and dopamine are just a few of these chemicals that are dysregulated in depression.

Donna Hill Howes, RN
Family Practitioner


Symptoms of depression can vary depending on the person and the type of depression. Catatonic depression is characterized by slow speech, the inability to do activities of daily living (ADLs). Melancholic depression, in which a person gets no pleasure from his or her usual activities, causes a person to become sluggish, sad, withdrawn, and show few emotions. Psychotic depression is characterized by false beliefs (delusions), hallucinations, hearing voices, and thoughts of death. Atypical depression may cause a person to be anxious and fearful in the evening, experience changes in appetite, gain weight, and become agitated, restless, and chatty.

Dr. Michael T. Murray, ND
Naturopathic Medicine Specialist

Depression is characterized by feelings of low self-esteem, pessimism, and despair. It can range from a transient "low mood" to a potentially life-threatening, severe clinical depression.

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Depression is an illness that encompasses all aspects of life. It impacts the way you behave, your mood, and your thoughts. It affects your eating habits, your patterns of sleep, the way you feel about yourself, and the way you see, think about, and perceive things.

The Diagnostic and Statistical Manual of Mental Disorders, or DSM, is a book that provides criteria for diagnosing the various mental illnesses. It defines a major depressive episode as a period of at least two weeks of depressed mood or the loss of interest or pleasure in most activities. In addition, to meet criteria for a major depressive episode, a person must experience at least four other symptoms from a list that includes things such as changes in appetite or weight; changes in sleep; decreased energy; feelings of worthlessness or guilt; difficulty thinking, concentrating, or making decisions; recurrent thoughts of death; or suicidal thoughts, plans, or attempts. Major depression affects your ability to function in many aspects of your life.

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To know if you have depressions, answer these questions:

  • Do you frequently feel sad, irritable, or quick to anger?
  • Have you stopped enjoying your hobbies and other things you used to enjoy?
  • Do you feel guilty or hopeless, or worry too much?
  • Do you feel out of energy or just prefer to sit alone more than usual?
  • Have you stopped participating in social events with your family or friends?
  • Are you sleeping too long or having trouble getting to sleep?
  • Have you experienced an unintentional 10-pound change in your weight?
  • Do you have thoughts of suicide or death?

Talk to your doctor if you answered "yes" to the last question, or "yes" to at least two of the others. These feelings can be symptoms of depression. They can also be caused by other health problems, such as anemia, thyroid disease, medication side effects, or other medical conditions.

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We all experience the blues or down moods once in a while, but when these feelings persist and compromise our daily functioning, it can be a sign of depression. Generally, depression is classified into three main categories:

  • Major Depression: This is an episode that lasts longer than two weeks and exhibits at least five of the seven following symptoms: Sleep alteration, decreased interest in activities, feelings of guilt, decreased energy, difficulty concentrating, alteration in appetite, thoughts of suicide. One common symptom: early-morning awakenings (we're talking 3:30 am, not 5:15 am when the alarm clock buzzes at 5:35 am anyway).
  • Situational Depression: This describes an episode that lasts longer than two months with the above symptoms, but comes after a person has suffered a significant life change, such as bereavement or retirement. Importantly, your symptoms improve with time since the major event, so most therapists feel that your long-term functioning is better if you can manage to get through this without drugs.
  • Vascular Depression: This is depression that commonly occurs after a brain or blood-vessel disorder, such as a stroke, or after a heart attack or heart surgery. Patients with lesions in the left hemisphere of the brain, especially of the left prefrontal cortex, tend to have increased frequency and severity of depression. The greatest risk period of depression following a stroke appears to be the first two years afterward, peaking within the first three to six months.

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Many people will describe themselves as being depressed at some time in their life. The word "depression" is often used in place of "disappointed" or "sad." You might say you are depressed because you didn't get the job you wanted, or because your latest romantic relationship did not work out. In the field of psychology, depression refers to a spectrum of mood disorders that result in clinical impairment and reduced level of functioning.

Someone who experiences clinical symptoms of depression may be diagnosed with a major depressive disorder, a dysthymic disorder, bipolar disorder, or cyclothymia, all of which are separate diagnoses. Bipolar disorder involves depression alternating with manic episodes, which are periods when a person feels elated and has an enormous amount of energy that may get him or her into trouble. Cyclothymia indicates a chronic alternation between low-grade depression and low-grade mania. Dysthymia is a diagnosis in its own right indicating a low-grade, unremitting depression. In general, these more complex mood disorders are more likely to be biologically based and require medical management.

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Although it may not show, depression contains an underlying component of fear and anxiety. Depression is pain directed against the self. Looking at depressed people's facial expressions, you immediately read how dull, withdrawn, exhausted, and sad they feel.Their approach to life is passive and resigned. We tend to forget this and treat depression as a weakness, particularly our own; if others can find joy in life, then it's our fault that we have failed to. Such judgments get connected to guilt, and depressed people are often acutely aware of letting down family and friends. They see themselves as the gray cloud threatening every happy occasion.

If you look at depression without judgment, it can be seen as the final battlefront against fear. Depressed people are on the verge of giving up, and indeed some will make the perilous choice of trying to end their lives. But before that stage, depression is a last line of defense, in which the mind runs for cover, shutting all operations down to a minimum, providing just enough life support for survival. Although it has become so commonplace that the word "depression" falls from our lips carelessly, as though we were discussing the flu or a bad headache, I can't escape its deep pathos. To me, seeing a depressed person is like watching a magnificent racehorse that has broken its leg. So much magnificence is possible for a human being that to see it shut down and almost extinguished is heartbreaking.

Two of the most common forms of depression are:

  • Major depressive disorder: disabling symptoms that prevent normal functioning. A person might experience only one episode of major depression or might have recurring episodes.
  • Dysthymic disorder: long-term (more than two years) less-severe symptoms that prevent the person from feeling well or normal.

Less common forms of depression include:

  • Seasonal affective disorder (SAD): depression during the winter months, when there is less natural light. Half of people who have SAD respond positively to light therapy; others might need medication plus light therapy.
  • Bipolar disorder: a cycling of mood changes, from extreme highs to extreme lows. An example would be not sleeping for days and performing high-risk activities, then becoming very depressed and not doing anything for months.

Below are the common types of depression:

  • Major depression is characterized by a combination of symptoms that interfere with the ability to work, study, sleep, eat, and enjoy once pleasurable activities.
  • Dysthymia, a less severe type of depression, involves long-term, chronic symptoms that are not disabling, but keep one from functioning well or feeling good.
  • Bipolar disorder (also known as manic-depressive illness) is not nearly as prevalent as other forms of depression.
  • Seasonal affective disorder (SAD) is a major depression that occurs in the winter when the amount of sunlight is limited.
  • Postpartum depression occurs within four weeks of childbirth. Most new mothers suffer from some form of the "baby blues."
  • Psychotic depression is a rare form of depression characterized by delusions or hallucinations, such as believing you are someone you are not and hearing voices.

There are multiple variations of depression that a person can suffer from, with the most general distinction being depression in people who have or do not have a history of manic episodes.

  • A depressive episode involves symptoms such as depressed mood, loss of interest and enjoyment, and increased fatigability. Depending on the number and severity of symptoms, a depressive episode can be categorized as mild, moderate or severe. An individual with a mild depressive episode will have some difficulty continuing with ordinary work and social activities but will probably not cease to function completely. During a severe depressive episode, on the other hand, it is very unlikely that the sufferer will be able to continue with social, work or domestic activities, except to a very limited extent.
  • Bipolar affective disorder typically consists of both manic and depressive episodes separated by periods of normal mood. Manic episodes involve elevated mood and increased energy, resulting in over-activity, pressure of speech and decreased need for sleep.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.