What Is Depression?

Key points
- Depression is an illness that involves feelings of sadness lasting for two weeks or longer, often accompanied by a loss of interest in life, hopelessness, and decreased energy.
- It is very different from a temporary case of "the blues" triggered by an unhappy event or stressful situation.
- Depression affects the mind, but this doesn't mean "it's all in your head.
- Being depressed doesn't mean a person is inadequate.
Depression is an illness that involves feelings of sadness lasting for two weeks or longer, often accompanied by a loss of interest in life, hopelessness, and decreased energy. Such distressing feelings can affect one's ability to perform the usual tasks and activities of daily living.
This is considered to be clinical depression. It is very different from a temporary case of "the blues" triggered by an unhappy event or stressful situation.
Depression affects the mind, but this doesn't mean "it's all in your head." Depression is a medical illness linked to changes in the biochemistry of the brain.
Depression is not a weakness of character. Being depressed doesn't mean a person is inadequate. It means the person has a medical illness that is just as real as diabetes or ulcers. Like other medical disorders, clinical depression should not be ignored or dismissed. A clinically depressed person cannot simply "snap out of it" any more than a person with an ulcer could simply will it away.
- But depression is highly treatable in the vast majority of cases. Up to 90% of depressed people respond positively to treatment. Sometimes psychotherapy or counseling is all that is needed, but there is also a wide array of effective antidepressant medications and alternatives available.
Clinical depression is an umbrella term used to describe the most common forms of depression, which include:
- Major depression, also known as melancholia or unipolar depression, can last up to a year if not treated. A person experiencing an episode of major depression will experience some physical problems, such as headaches or digestive upset, in addition to emotional difficulties.
- Bipolar disorder, once called manic depression, causes mood swings that soar to unusual elation, and then plummet to depression. A person with severe bipolar disorder may also see or hear things that are not there and experience paranoia (a feeling that they are in danger).
- Dysthymia is a chronic (ongoing), low-grade depression. It often begins in childhood or adolescence and may last for many years in adulthood if not treated. It is a less severe form of clinical depression, but at times it can be almost as disabling as major depression.
- Seasonal affective disorder (SAD) is a form of depression thought to be triggered by a decrease in exposure to sunlight. In the Northern Hemisphere, the condition usually occurs in late fall and winter, when daylight hours are short, and it is more common in geographical areas that have four clearly defined seasons.
Nice To Know:
Perhaps nowhere is the connection between mind, body, wellness, and illness more striking than in depression. It is now believed that human emotions, including sadness, elation, and anxiousness, are governed to some extent by chemical reactions in the brain. That is only the beginning. Scientists have only recently begun to unravel the complex interplay between factors that contribute to depression. Illness, heredity, psychological traits, and social environment are all believed to play a role.
Written and revised by
David Cohen, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
health.am provides general information, not medical advice. Always consult a qualified health professional about your own health.
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