“People with depression may experience a lack of interest and pleasure in daily activities, significant weight loss or gain, insomnia or excessive sleeping, lack of energy, inability to concentrate, feelings of worthlessness or excessive guilt and recurrent thoughts of death or suicide”
www.apa.org (American Psychological Association,2015)
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What is American Psychological Association
What is because it is updated (2015), it comes from a trustworthy organization, the source is listed