A recent study looked into the long-term effects of watching too much television as a toddler. Somewhat surprisingly, the impact could be measured in the children's dietary habits, weight, and behavior as teenagers.

Are there any long-term impacts of watching TV as a toddler?

Paradoxically, in this fast-paced modern world we live in, humans are more and more inclined to sit for long periods of time staring at screens.

This shift in habits is considered by many to have a negative impact on our children.

Though most parents try to limit the amount of screen time that their children have, the ever-growing number of screens per household is making it more and more challenging.

For instance, around 1 in 3 infants in the United States have a television in their bedroom, and nearly half of all children watch television or DVDs for almost 2 hours each day.

Screen time and negative outcomes

Evidence is mounting that screen time has a negative impact on children as they develop. Because watching TV is sedentary both physically and mentally, connectivity may be disturbed in the rapidly developing toddler brain. Also, it has the potential to set up negative habits for later life — choosing easier, less demanding activities over physically or mentally challenging pastimes, for example.

Studies have revealed that increased screen time for toddlers and kindergarten children increases the risk of having a higher body mass index (BMI) and waist circumference as they enter the first grade. Other studies have found that waist circumference and physical fitness are adversely impacted as children enter fourth grade.

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Off the back of these findings, in October 2016, the American Academy of Pediatrics reduced the guidelines for television viewing in children aged 2–5 years to no more than 1 hour per day.

Although there is little debate that excess television viewing has unfavorable health consequences, the impact of early TV viewing on behavior as the child enters their teens is less known. It was this direction that a team of Canadian researchers recently took. In particular, they were interested in lifestyle outcomes, such as school performance and dietary choices.

The researchers were led by Prof. Linda Pagani and graduate student Isabelle Simonato, from the School of Psychoeducation at the Université de Montréal in Canada. They took data from the Quebec Longitudinal Study of Child Development.

Early TV viewing's effect on teens

In total, almost 2,000 boys and girls born in Quebec in 1997–1998 were involved in the study. The children had been followed from the age of 5 months.

Parents reported TV habits as they grew, then, when the children reached the age of 13, they self-reported dietary habits and behavior at school. Prof. Pagani explains why this study is particularly useful, saying, "Not much is known about how excessive screen exposure in early childhood relates to lifestyle choices in adolescence."

"This birth cohort is ideal, because the children were born before smartphones and tablets, and before any pediatric viewing guidelines were publicized for parents to follow. They were raising their children with TV and seeing it as harmless. This makes our study very naturalistic, with no outside guidelines or interference — a huge advantage."

As expected, there were measurable effects of increased TV time on habits as the children entered their teenage years. The team's results were published earlier this month in the journal Preventive Medicine.

Each additional hour of TV viewing at the age of 2 predicted significantly worse eating habits at the age of 13. They consumed more prepared meats and cold cuts, French fries, white bread, soft and fruit-flavored drinks, sports and energy drinks, sweet or salty snacks, and desserts.

Toddlers who watched more TV were more likely to skip breakfast on school days as a 13-year-old.

Also, these children were less likely to make an effort in their first year of high school, which had an adverse effect on performance and ambition. As a 2-year-old, each additional hour spent watching television per day predicted a 10 percent increase in BMI at age 13.

How does TV have such an effect?

Simonato believes that it is the sedentary nature of TV watching that might be to blame for some of the findings. She explains, "We hypothesized that when toddlers watch too much TV it encourages them to be sedentary, and if they learn to prefer effortless leisure activities at a very young age, they likely won't think much of non-leisure ones, like school, when they're older."

"This study tells us that overindulgent lifestyle habits begin in early childhood and seem to persist throughout the life course. An effortless existence creates health risks."