A Cambridge University report, published in the International Journal of Behavioural Nutrition and Physical Activity found that teens who spend an extra hour a day surfing the internet, watching TV or playing computer games risked performing two grades worse in exams than their peers who don’t.
A study of more than 800 students aged 14 and 15, also found that physical activity had no effect on academic performance, thus confirming that psychopathic PE teachers were the chocolate teapots of academia.
Researchers followed the pupils over time to see how different behaviours affected performance.
The scientists said it was reasonable to conclude that too much screen time reduced academic achievement.
Kirsten Corder of Cambridge’s Centre for Diet and Activity Research, who co-led the work said that it is possible to reasonably suggest that screen time may be damaging to a teenager’s grades.
The study found the average amount of screen time per day was four hours.
An extra hour in front of the TV or online at age 14-and-a-half was linked with 9.3 fewer exam points at age 16 — equivalent to two grades, for example from a B to a D. Two extra hours was linked to 18 fewer points.
Pupils doing an extra hour of daily homework and reading scored better had averages of 23.1 more points than their peers.
Further research was needed to confirm the effect conclusively, but advised parents worried about their children’s grades to consider limiting screen time.
It is not all tablets and mobiles though. TV was the most detrimental in terms of exam performance.