Children are still being exposed to “junk” food advertising on TV despite a ban during popular programmes for the under-10s being in force for the past eight months.

The advertising restrictions are to be extended to programmes that are watched most by under-16s from January. But research from the consumer watchdog, Which? has found that the advertising ban is not working and that the new restrictions to protect young teenagers from promotions for foods high in fat, sugar or salt will have little impact.

The organisation gives warning to-day that 12 of the 20 programmes most watched by children under 10 are not covered by the ban.

Even when the restrictions are extended to protect the under16s, only two of their top 20 programmes would have a ban on junk food promotions.

The findings are important because just a few weeks ago Gordon Brown acknowledged the need to curb the promotion of “inappropriate foods” to help to tackle the obesity crisis.

The campaign group is demanding urgent action now to toughen up the rules on junk food promotion.

Which? says the problem is that junk food advertisements are banned only if an audience has a 20 per cent higher proportion of viewers in the under10 or under16 age group than the rest of the population.

This means that many foods high in fat, salt or sugar can be freely promoted during favourite family shows such as The X Factorand Ant and Dec’s Saturday Night Takeaway because, even though these are watched by most children, adults are the highest number in the audience.

Junk food adverts are banned during The Simpsons because it has a child audience of 163,200. However, the ads are shown during The X Factor, which has 442,300 child viewers.

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