Professor Annie Anderson, director of the Centre for Public Health Nutrition Research at Dundee University, says eating junk food in public should be stigmatised in the same was as smoking.

The nutritionist, who has advised the Scottish executive on school meals, believes that people should be banned from eating burgers and chips on public transport and that supersize portions of fizzy drinks and popcorn should be phased out in cinemas.

She argues that the ready availability and low cost of junk food is fuelling soaring obesity rates. More than one in five Scots adults are obese while more than a third of 12-year-olds are overweight, almost a fifth are obese and one in 10 is severely obese. Last week The Sunday Times revealed that Nitshill in Glasgow had been identified as the fat capital of Scotland. A quarter of local residents are at least two stone overweight, according to a survey carried out by CACI, the London-based market research group.

Anderson believes that lessons should be learnt from the campaign that led to smoking being banned in enclosed public places and that the typical Scots diet, which is high in fat, sugar and salt, poses a similar threat to public health.

“There are areas of temptation like the cinema where it’s part of the whole experience, a bucket of coke or popcorn. It’s sedentary behaviour and eating to excess,” she said.

“Maybe we should make sure that no supersize options are available and scale it down. In cinemas it could be they wouldn’t have (fizzy) drinks, just diet ones. This would decrease the opportunities of increased calorie intake.”

Although Anderson said she wasn’t “gunning for a nanny state”, she added that it was time for Scots to take responsibility for their diet and recognise its impact on their health. She added that the social acceptability of eating fast food in public, such as on buses and trains, had to be challenged.

“When you visit other countries they have the food sign crossed out on public transport,” she said. “The opportunities to eat high-calorie food need to be curtailed. If we limit it, then over time there’s every opportunity for improvement in health.”

Anderson’s call follows a new study dismissing lack of exercise and television watching as the reason for Scotland’s alarming childhood obesity rates. Instead, it suggests that diet is to blame.

The study by Norwegian researchers, published in the European Journal for Public Health, examined the viewing and exercise habits of nearly 50,000 young people in seven countries including Scotland, Norway, Austria and Sweden between 1986 and 2002. It found that while the proportion of Scots teenagers watching more than four hours of television a day dropped by 7% and physical activity rose by 4%, obesity rates continued to rise.

The Scottish executive said: “Obesity is not the consequence of a single factor and as such it is important not to look at the impact of physical activity in isolation from other factors such as diet. “Behaviour change does not happen overnight and cannot happen through government action alone. However, we are confident that our approach to tackling obesity is the right one.”

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