CHILDHOOD is an important time for good TV viewing habits, as the amount watched could be crucial to reducing negative health effects during adulthood, according to a new study.
The TV watching habits of nearly 2,500 individuals from childhood to adulthood, were studied by researchers from Curtin University’s Department of Physiotherapy and Exercise Science as a part of the Raine Study.
‘Subgroups’ with particular viewing habits were identified, some which were associated with increased body fat and physical activity levels, Post-doctoral Research Fellow Dr Jo McVeigh says.
There exists a subset of people (roughly one-third of the study group) who watch low amounts (less than 14 hours per week) of TV during childhood, but then who increase the amount of TV they watch over the adolescent period (to greater than 14 hours per week), she says.
“Despite this increase in TV watching over the adolescent period, this group still had a lower percentage of body fat at age 20 than the group of people who had watched consistently high levels of TV from childhood to adulthood.”
In the other two-thirds of the group, TV watching appeared to be a relatively stable behaviour over time and showed an association between increased body fat and TV watching, especially for females.
It’s definitely worth promoting watching less than 14 hours of TV per week, particularly in childhood and during adolescence Dr McVeigh says.
Our caloric intake is increased through between-meal snacking while watching TV and that the time spent being sedentary while watching TV is likely to be displacing time that could be spent being physically active, evidence suggests.
“It’s likely to be a combination of things—those who spend less time watching TV as children may be more likely to have lower caloric intakes, be making healthier food choices and being more active and these healthier habits are likely to track into adulthood.”
“On the other hand, repeated exposure and accumulation of high levels of TV watching over time may contribute to obesity and this may start in early childhood,” she said.
The effects may be even greater if more sedentary time is spent interacting with other ‘screens’ such as e-mail, messaging, surfing the Internet and playing electronic games, Dr McVeigh warns.
Data were collected from 2411 participants (50/50 male/female) from the Raine Study, the Western Australian Pregnancy Cohort. Participants were followed up over 15 years and answered questions about hours of TV watching per week at six time-points (5, 8, 10, 14, 17 and 20yrs).