All of us feel sad or depressed at some point or other but the feeling usually passes after a while. But in depression the low feeling or feeling sad interferes with the person’s daily life and normal functioning to such an extent that both the concerned person and people around them are affected by it.

MediLexicon's Medical Dictionary defines depression as "A mental state or chronic mental disorder characterised by feeling of sadness, loneliness, despair, low self-esteem, and self-reproach; accompanying signs include psychomotor retardation (or less frequently agitation), withdrawal from social contact, and vegetative states such as loss of appetite and insomnia."

Depression does not affect only the mood but is a "whole-body" illness, which affects the body, mood, and thoughts. Depression affects everything right from the way you eat and sleep, feel about yourself, and think about things. Many people think that a person who suffers from depression is a weak individual who does not know how to handle problems and stress. But it should not be considered as a sign of personal weakness or a condition that can be controlled by just being strong in the mind.

A person with depression cannot just "pull himself together" and start feeling better. If the person is not treated the symptoms can last for weeks, months, or years. However, appropriate treatment can be very beneficial for most people who suffer from depression.

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