Jowell, secretary of state for culture, media and sport, is speaking today at the ISBA annual conference. A report in the Financial Times says that she will tell advertisers that they must "prove again that advertising need not be an adversary of those who want a healthier Britain".
She will reject calls for a ban in favour of voluntary regulation. Also ruled out, according to reports, are "tombstone" warnings on food packaging.
With obesity rising, there is a growing battle between advertisers and pressure groups about the issue of banning ads for junk food to children.
The charity Sustain, which campaigns on food and farming standards, is coordinating a call for a ban on junk food advertising and said yesterday that it had signed up 106 organisations in favour of the ban. These include the Children's Society, the Consumers' Association and the Royal College of Surgeons.
On the one side, the food and drink industry argues that the advertising on which they spend millions of pounds does not make children eat more. On the other hand, researchers claim that obesity is becoming a bigger problem because children lead sedentary lifestyles and that the real issue is to encourage people to be more active, as well as eating a balanced diet.
Jowell is to tell advertisers at today's conference to come up with positive messages and turn the phrase "everything in moderation" into a slogan.
She will say: "I know you can do it. You are the people who made condoms sexy again."
The Food Standards Agency is due to agree its policy recommendations on the promotion of food to children next week, which it will then present to the government.
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