Carnegie Mellon University scientists say there's growing evidence positive emotions such as happiness are linked with good health and increased longevity.
But the Pittsburgh researchers say a review of research conducted during the past decade finds too many questions remain unanswered to draw definitive conclusions.
The strongest links between positive emotions and health were found in studies examining "trait" emotions, which reflect a person's typical emotional experience, rather than "state" emotions, which reflect momentary responses to events.
The researchers say people who typically report more positive emotions experience lower rates of chronic illness, symptoms and pain. Moreover, among elderly people who live by themselves or with family rather than in retirement homes, positive emotional dispositions are linked with living longer. In contrast, positive emotions are not associated with increased longevity in studies of other populations.
Although possibly beneficial for recovery from less serious diseases, extremely positive emotions are in some cases associated with poorer outcomes among those with serious illness.
The study appears in the Dec. 12 issue of the Psychological Bulletin.
Copyright 2005 by United Press International
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