This is why junk food advertising during television shows aimed at young people is considered by many nutritionists to be a bad thing: a study conducted in the UK finds that the average difference in consumption between kids exposed to six and seven adverts a week is 350 calories.
The study, conducted by a team led by Jyotsna Vohra of charity Cancer Research UK, will be presented at the European Congress on Obesity, held in Vienna, Austria in late May.
The research involved 3300 youths aged between 11 and 19 years.
To make their findings the researchers asked the volunteers to describe their weekly viewing habits, estimating the number of hours spent watching commercial television and streaming services. They were also asked about what fast food adverts they remembered, brand awareness, and reactions.
Vohra and colleagues used a standardised metric to estimate the number of junk food adverts to which participants were exposed. The average viewing time for the volunteers was 21 hours each week, meaning they likely saw six ads.
Young obese volunteers, however, watched 26 hours each week, during which time they were exposed to one extra advert.
Questions about food intake revealed that the kids who saw the extra advert consumed extra fast food – to a total amount of 18,000 calories across a full year.
Even for the kids in the average cohort, however, junk food consumption was very high. The researchers found that on average they consumed 30 high fat, salt and sugar items each week, accounting for between 40% and 50% of their recommended total calorie intake.
The study also found that children who were most familiar with junk food advertising ate more of the products and carried more weight. The relationship remained robust even after factors such as age and gender were taken into account.
Kids from lower socio-economic backgrounds were the most likely to recall fast food adverts.
“This combined with their already greater risk of unhealthy weight outcomes suggests that young people from deprived backgrounds would potentially have the most to gain from regulation designed to reduce junk food ad exposure,” says Vohra.