First we learned that obesity appears to spread though social networks; now comes a report from researchers at Harvard claiming that depression does the same thing. The researchers tracked evidence of depression in a social network of 12,067 people who were part of the Framingham Heart Study for more than 32 years. An abstract in Molecular Psychiatry reports that depression was “strongly correlated” with depression in friends and neighbors, and extended up to three degrees of separation–friends of friends of friends. The researchers found that female friends were “especially influential in the spread of depression from one friend to another.”
Read an abstract of the study in Molecular Psychiatry.