Obese and overweight children who watch food adverts on TV more than double their food intake afterwards, new research suggests.
A study from the University of Liverpool also found that children of normal weight upped their eating by 84 per cent.
Researchers studied 60 children of different weights aged between nine and 11.
They were shown a series of food adverts and toy adverts, followed by a cartoon.
The amount of eating following the food adverts was significantly higher than following the toy adverts, the study found.
Obese children increased their consumption by 134 per cent; overweight children by 101 per cent and normal weight children by 84 per cent.
Earlier this year, Ofcom announced that TV adverts promoting unhealthy food and drinks would be banned during programmes aimed at children up to the age of 16.
Advertising for products which are high in fat, salt and sugar, and which particularly appeal to children, must not be shown in or around programmes for those under 10 from this month.
From the beginning of January 2008, a total ban will come into force for advertising junk food during programmes aimed at or which appeal to under-16s.
The restrictions apply to food and drinks products which are assessed as being high in fat, salt and sugar (HFSS) by the Food Standards Agency.
This new study found exposure to food adverts increased the children’s intake of all foods except a low-fat savoury item.
The foods offered to the group were Snack a Jacks (low-fat savoury), Walkers crisps (high-fat savoury), Haribo jelly sweets (low-fat sweet), Cadbury buttons (high-fat sweet) and a bunch of grapes.
Overweight children mainly increased their intake of chocolate and jelly sweets, and obese children mainly increased their intake of chocolate.
Dr Jason Halford, director of the university’s Kissileff Laboratory for the study of Human Ingestive Behaviour, said: ‘Our research confirms food TV advertising has a profound effect on all children’s eating habits – doubling their consumption rate.
‘The study was also particularly interesting in suggesting a strong connection between weight and susceptibility to over-eating when exposed to food adverts on television.’
The university research team is presenting its findings at the European Congress on Obesity in Budapest this week.
Which? food campaigner Miranda Watson said: ‘There is clear evidence to show that tight restrictions are needed to protect children from unhealthy food advertisements on TV yet the restrictions in place will not cover the programmes that most children are watching. Which? is calling on the Government to step in and tighten the restrictions as a matter of urgency.’