The British Heart Foundation has called for restrictions on TV advertising for unhealthy products.
The suggestion was made in a report from Academy of Medical Royal Colleges on the UK’s obesity crisis.
The report said Britain is the ‘fat man’ of Europe.
Latest figures from the Health Survey for England 2009-11 shows that one quarter of men and women are obese (BMI over 30) and two thirds of adults are obese or overweight (BMI over 25).
The National Child Measurement Programme 2011-12 shows that for children aged 10-11, one in five are obese and one in three are overweight or obese.
In the last 20 years, the number of morbidly obese adults (BMI over 40) has more than doubled to over one million UK citizens.
Maura Gillespie, Head of Policy and Advocacy at the BHF, said: “A ban on junk food ads before 9pm would be a step towards a healthier future for today’s children. As a parent, I would be more confident knowing that adverts for unhealthy food weren’t allowed to pervade prime time.
“Obese children are more likely to become obese adults, so the lessons we learn about diet at a young age can have implications for our health in later life.
“Restrictions on TV advertising for unhealthy products have reduced the number of junk food ads children see. But these rules only cover kid’s TV specifically, so marketers can still advertise these products during some of the UK’s biggest family shows.
“Screening junk food adverts after the watershed, along with consistent regulations across all media, including online, will prevent children from being easy targets for junk food marketers.”
The Academy of Medical Royal Colleges also called for a 'minimum price' increase of 20% on sugar-sweetened drinks.