Health-related Internet use was associated with small but reliable increases in depression (i.e., increasing use of the Internet for health purposes from 3 to 5 days per week to once a day was associated with 0.11 standard deviations more symptoms of depression, P = 0.002).
Using the Internet for health purposes was associated with increased depression. The increase may be due to increased rumination, unnecessary alarm, or over-attention to health problems.
In contrast, using the Internet to communicate with friends and family was associated with declines in depression.
Effects of Internet Use on Health and Depression: A Longitudinal Study. J Med Internet Res 2010;12(1):e6.
Negative consequences from the use of internet for health information - CDC (PDF) http://goo.gl/Fgcq via http://goo.gl/947F
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