Too much television affects vision beyond square eyes

CHILDREN spending hours a day in front of the TV have narrower retinal arteries, which could indicate future cardiovascular risk, Sydney researchers say.

A study of more than 1700 six-year-olds from 34 schools found the most active, sporty children had a retinal arteriolar calibre on average 2.2 microns wider than the least active children. Sedentary children indulging in a lot of “screen time” had narrowed arterioles, according to the authors.

“The magnitude of arteriolar narrowing associated with each hour daily of TV viewing is similar to that associated with a 10 mmHg increase in systolic blood pressure in children,” they said. 

Arterioscler Thromb Vas 2011; 31:1233-39