http://www.bbc.co.uk/news/science-environment-11340881
I think the article's title is a little misleading, of course. It says, "Cognitive psychologist Dr Tracy Alloway from the University of Stirling, who was not involved in the latest study, said that some people have a tendency to brood too much and this leads to a risk of depression." Obviously, excessive brooding / worrying exerts un-needed stress on one's health.
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