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A slender person with overweight friends is more likely to gain weight than one whose buddies are svelte. That’s the conclusion of a new study that mined 30 years’ worth of data and found that obesity correlates strongly with social networks.3quarksdaily: Six Degrees of Obesity? (note: I saved that link when it came out, in 2007; since then, there has been a lot of work from Andrew Gelman and others to show that the findings of Fowler and Christakis are less robust than claimed in some parts of their analysis)
