Junk food ads leading to heavier kids: McMaster study

Researchers at McMaster University are craving change after findings show the effect of junk-food marketing on children's eating habits.

Researchers crave change after findings show effect of marketing on children's eating habits

New research from McMaster University reports that junk-food advertising has a clear affect on children's food choices and consumption. (Associated Press)

Researchers from McMaster University are warning against the power of advertising to kids.

A study in the scientific journal Obesity Reviews, discovered that junk-food ads increased the amount of unhealthy food and beverage choices children made, as quickly as thirty minutes after exposure to the ad.

The increase has been astronomical. It's one of the major healthcare crises that we're faced with.- Bradley Johnston, McMaster University

In other words, Saturday morning cartoons and cereal are a more dangerous combo than previously thought.

Led by PhD student Behnam Sadeghirad, the study analysed 29 randomized trials that together provided data from more than 6,000 children. They looked at the marketing of unhealthy foods and beverages through numerous media platforms.

"The extensive exposure kids have to marketing of unhealthy foods and beverages via product packaging, TV and the Internet increases their short-term caloric intake and preference for junk food," said Sadeghirad in a press release.

Bradley Johnston co-authored the study of marketing's influence on childhood obesity. (McMaster University)

A Canadian crisis

As of 2011, Statistics Canada reported that more than a quarter of all children from 5-17 years old in Canada have a BMI that classifies them as overweight or obese.

"The increase has been astronomical over the last 10-20 years," said co-author Bradley Johnston, Scientist at The Hospital for Sick Children and Assistant Professor at McMaster University.

"It's one of the major healthcare crises that we're faced with."

Research has also revealed that today, children are exposed to an average of five food ads per hour, and that unhealthy foods account for more than 80 per cent of all televised food ads in Canada, the U.S. and Germany.

A study of more than 29 randomized trials revealed that advertising influence's children to make unhealthy food and beverage choices almost immediately after watching. (Rich Pedroncelli/Associated Press)

Media-induced munchies

Results showed that unhealthy food choices were higher in children almost immediately after exposure to junk food ads.

In fact, the study looked at the choices children made up to 30 minutes after exposure to junk-food advertising. Children that were exposed to ads consumed 30 calories more than children who were not in that short time period.

And the power of marketing for children is no joke.

A recent study out of Ohio State University found that marketing vegetables as superheroes in school cafeterias as much as tripled the percentage of students choosing the items from the salad bar.

The study used characters like Miki Mushroom, Zach Zucchini and Suzie Sweet Pea, labeled as the Super Sprowtz to advertise the various vegetables on display.

Lead research Andrew Hanks said that while marketing to children can be seen as controversial, it "can have both positive and negative effects. We can harness the power of marketing to help us."

It's a message that McMaster researchers heard loud and clear when it comes to advertising.

"It does have an impact on children in terms of how much food they consume and their food choices," Johnston said. 

Johnston says the next steps are a matter of education and knowledge sharing, to try and combat childhood obesity in Canada. (Jake May/Flint Journal/Associated Press)

When a child watches TV for an hour, he said, they're exposed to on-average of five commercials for junk food. This "can really leave an impression on a child's mind."

Craving change

For Johnston, the next steps are clear; people need to know the effect marketing has on their children.

"Getting this information into the hands of parents, into the hands of clinicians, and into the hands of policy makers" is crucial, he said.

Currently Quebec is the only province with a strict code enforced to prohibit commercial advertising to children under 13-years-old. Incorporated in the Quebec Consumer Protection Act, the legislation has been in force since 1980. It's action Johnston would like to see elsewhere in Canada.

"There are no strong restrictions or regulations from the federal government," he said. "It's time for us to revisit federal policies and provincial policies."

Turning to research, Johnston is now curious about what comes after 30 minutes, when children are exposed to junk-food ads.

"We need to better understand what is the impact over the longer term," he said.

Research for this study was funded in part by the Heart and Stroke Foundation of Canada and the Canadian Institutes for Health Research Chair in Hypertension Prevention and Control held by Dr. Norm Campbell of the University of Calgary.


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