Children are encouraged to eat more junk food if it is endorsed by a celebrity, a new study has found.

According to UK scientists, celebrities are often used in television advertisements to induce children to choose certain foods. This type of endorsement is seen as an effective method of creating recognition and credibility for a particular product.

The team decided to look into this further by analysing the use of former England footballer, Gary Lineker, to endorse Walkers Crisps. Mr Lineker, who is now a sports presenter on television, has been endorsing the crisps since the mid 1990s. His work as a presenter on Match of the Day and the Walkers ads can be seen on Irish television.

The scientists from the University of Liverpool looked at 181 children aged between eight and 11. Each was asked to watch a 20-minute cartoon, during which one of three different advertisements or general footage of Mr Lineker presenting Match of the Day, was shown.

The three advertisements were for Walkers Crisps, another snack food and a toy.

The children were then offered two bowls of crisps to eat. While both contained Walkers, one was labeled as such, while the other was labeled as ‘supermarket'. The scientists measured the amount of crisps consumed from each bowl.

The study found that the children who had watched the Walkers advertisements featuring Mr Lineker, or the TV footage of him, ate significantly more of the Walkers Crisps compared to the children who watched the other ads.

The scientists said that this showed the power of celebrity endorsement even when the celebrity was seen on television in a different context, i.e. presenting a sports programme.

"This is the first study to show the powerful effects of celebrity endorsement - in both a TV advertising and a non-food context - on the choice and intake of the endorsed snack product over the same product offered as a non-branded snack item.

"The study demonstrated, for the first time, that the influence of the celebrity extended even further than expected and prompted the children to eat the endorsed product even when they saw the celebrity outside of any actual promotion for the brand," explained lead scientist, Dr Emma Boyland.

She added that this study ‘quantifies the significant influence that the celebrity has over children's brand preferences and actual consumption'.

Dr Boyland insisted that these findings ‘have consequences for the use of celebrities'. She said this was especially the case in relation to sports stars advertising products that contain high amounts of fat, salt and sugar.

"If celebrity endorsement of these products continues and their appearance in other contexts prompts unhealthy food intake, then this would mean that the more prominent the celebrity, the more detrimental the effects on children's diets," she added.

Details of these findings are published in the Journal of Pediatrics.