As usual, a study that finds an association needs to be followed by a study that uses a randomized controlled trial to establish causality. Quoting the paper:<p>"Participants reported time spent in TV viewing (mentally-passive sedentary behavior) and sitting during work or driving (mentally-active sedentary behavior) at age 44. Waist circumference, C-reactive protein, and glycated hemoglobin were also measured at age 44. Depression diagnosis was self-reported at ages 44, 46, 50, and 55.
]"<p>If you are unemployed and not in school and living alone, watching TV is a default activity. The cause of depression may not be watching TV but the circumstances leading to it. You could do a study where in the treatment group people's cable TV is turned off. I doubt it will make people happier.