That the problem exists is obvious; its nature and extent are not. Obesity can be measured on scales. But how to weigh an emotion? Researchers start by distinguishing several related conditions. Loneliness is not synonymous with social isolation (how often a person meets or speaks to friends and family) or with solitude (which implies a choice to be alone).
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Another villain in the contemporary debate is technology. Smartphones and social media are blamed for a rise in loneliness in young people.
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