Top English psychologist Dr. Aric Sigman said we must prevent children under three from watching television or risk irreversibly damaging their health, the Daily Mail reported. About 80 percent of brain development happens before we are three, and screen time at this age seems to be particularly damaging. So there needs to be a recommended daily allowance for screen time as we have with salt and fat.
Research suggests it is not what you watch, it is what age you start and how long you watch for that has a detrimental effect. In many ways Teletubbies, or any other educational program for children, could be as physiologically damaging as a violent video game.
In addition, a new study from the Heart and Diabetes Institute, Melbourne, found that each daily hour of TV viewing in adulthood was associated with an 18 percent increase in death from heart disease. Those who watched four or more hours were 80 percent more likely to suffer a fatal heart condition.

据英国《每日邮报》报道，英国顶尖心理学家埃里克·西格曼呼吁，孩子3岁之前应该禁看电视，否则会给孩子健康造成不可逆转的危害。孩子在3岁之前大脑发育完成大约80%，所以这个年龄段的孩子看电视对大脑的损害最严重。因此，有必要像限制食盐和脂肪摄入量一样对儿童每天看电视时间实行量化限制。

研究表明，看电视对儿童健康造成危害，关键问题不是电视节目内容，而是开始看电视的年龄以及看电视时间的长短。从多方面看，《天线宝宝》等很多儿童教育电视节目对儿童生理上造成的伤害与暴力游戏几乎没有区别。
此外，墨尔本心脏与糖尿病研究所的一项新研究发现，成年人每天看电视1小时，心脏病死亡危险增加18%；每天看电视4小时以上，致命心脏病危险增加80%。

英文科普