Introducing a stricter watershed on junk food advertisements could help curb childhood obesity, research suggests.
One in 10 (9.5%) four to five year olds in England are obese, rising to one in five (20.1%) among those aged 10 to 11.
Carrying an excessive amount of weight at a young age is associated with obesity in later life, raising the risk of heart disease, type 2 diabetes and even certain cancers.
Childhood obesity has also been linked to bullying and low self-esteem.
The UK government has announced ambitious plans to halve childhood obesity by 2030. In 2007, it introduced a watershed that prohibits the advertisement of junk food around “programmes of particular appeal to children aged four to 15 and on dedicated children’s channels”.
It is now considering going further by implementing a 9pm watershed across all programmes.
To better understand the potential benefits of this, scientists from the University of Cambridge looked at data on how exposure to junk food advertising affects a child’s calorie intake.
Results suggest if the advertisements were only aired between 9pm and 5.30am, obesity among five to 17 year olds could fall by 4.6% – equivalent to 40,000 children having a healthier body mass index (BMI).
“Our analysis shows introducing a 9pm watershed on unhealthy TV food advertising can make a valuable contribution to protecting the future health of all children in the UK, and help level up the health of children from less affluent backgrounds,” said lead author Dr Oliver Mytton.
“However, children now consume media from a range of sources, and increasingly from online and on-demand services, so in order to give all children the opportunity to grow up healthy it is important to ensure this advertising doesn’t just move to the 9pm to 10pm slot and to online services.”
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Despite the 2007 restrictions, advertisements continue to air around family-based shows, which are often watched by many children.
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The World Health Organization recommends restricting the number of junk food adverts viewed by young people, however, no country has yet introduced a 9pm watershed.
To learn more about its benefits, the Cambridge scientists analysed a range of studies that looked at children’s exposure to junk food advertising and how this affects calorie intake.
The results – published in the journal PLOS Medicine – suggest that if these advertisements were only aired between 9pm and 5.30am, the UK’s 3.7 million children would see on average 1.5 fewer junk food adverts a day.
This could reduce their daily calorie intake by an average of 9.1kcal, which would be expected to cut obesity among five to 17 year olds by 4.6% and the prevalence of overweight BMIs by 3.6%.
This is equivalent to 40,000 fewer children with obesity and 120,000 fewer being classified as overweight, according to the scientists.
From a financial perspective, the watershed could save the UK £7.4bn ($96.5bn) in healthcare costs, they added.
“Measures which have the potential to reduce exposure to less-healthy food advertising on television could make a meaningful contribution to reducing childhood obesity,” concluded the scientists.
They pointed out, however, “this is a modelling study and we cannot fully account for all factors that would affect the impact of this policy if it was implemented”.
Caroline Cerny from the Obesity Health Alliance added: “There is no doubt our day to day choices are influenced by the advertisements we are subjected to.
“That is why food companies spend millions on advertising every year, to make sure their products are centre stage in our minds.
“A 9pm watershed will stop junk food adverts dominating our TV screens, and in turn, will have a huge impact on children’s health.
“It is of the utmost importance we give our children the chance to grow up healthy, without being at an increased risk of physical and mental health problems associated with obesity.”
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