Is an hour worth 22 minutes?
A team of Australian researchers has calculated that every hour of TV you watch past the age of 25 cuts your life expectancy by up to 22 minutes -- even if the hour isn't spent watching "Jersey Shore."
In fact, the scientists found, TV viewing may rival smoking, obesity and lack of physical activity as a threat to public health.
Of course, it took quite a bit of statistical heavy lifting to reach this conclusion, which shows only that TV and earlier death go together, but not that one causes the other. In all likelihood what the scientists are measuring isn't the health effect of TV watching. It's the health effect of a sedentary and perhaps isolated lifestyle. Studies suggest that sitting a lot is bad for you, even aside from whether or not you exercise, and that unhappy people watch more TV.
That a sedentary life is bad for you can't be shocking news to American adults, who watch television an average of five hours a day. Surely, from one program or another, they've heard they ought to move around more and eat less. The challenge is getting themselves to do it. Maybe this is why exercise videos were invented -- so people could watch and move at the same time.
TV watching has been studied to death. It would be interesting for a change to read a study of people who sit around and read a lot of books. Scientists may yet discover that this will shorten your life as effectively as sitting in front of the tube -- unless, of course, you read a book while out riding a bike, in which case it will shorten your life even more.