MOST Scots are vastly underestimating how heavy a person has to be before they are considered obese, with many also not realising their own weight has become a health risk.

A survey of attitudes to obesity among a nationally representative sample of 1200 Scots found that only 29 per cent were able to identify an obese body shape when asked to look at a series of ten computer-generated images of male and female figures who were gradually gaining in weight.

Most chose images which were well beyond the threshold for obesity.

HeraldScotland: Pic: NHS Health Scotland Pic: NHS Health Scotland

(H is the first 'obese' image for both the male and female chart; but most Scots thought it was I or J)

HeraldScotland: Pic: NHS Health Scotland Pic: NHS Health Scotland

Similarly, fewer people in the survey group described themselves at being "very overweight" than would have been expected based on population data on the height and weight of Scottish adults.

Read more: See Camley cartoon

The researchers said this showed that the public's perception of an "obese" person is out of step with the medical definition, and was therefore "not a useful term" for public health messaging.

They said: "Obesity was not well recognised. People generally identified obese people as those who were much more overweight than the medical definition of obesity. There was also a difference in how obesity in men and women was identified. Men needed to be more overweight than women to be recognised as obese."

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The Scottish Attitudes Survey, by NHS Health Scotland, also found that most respondents believed smoking and drinking is a bigger health risk than being obese, with fewer than half (43 per cent) realising that obesity increases a person's chances of developing a number of cancers. Only around a third knew being obese also raises the risk of infertility, asthma and liver disease.

In comparison, there was much greater awareness of obesity's links to heart disease, high blood pressure and diabetes, with roughly nine in 10 respondents acknowledged.

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While 85 per cent of those polled said it was mainly up to individuals to reduce their own weight, there was also widespread support for interventions such as the sugar tax on fizzy drinks (62 per cent support), banning junk food and confectionary from supermarket checkouts (backed by 66 per cent) and limits on the amount of fat, sugar and salt which manufacturers should be allowed to add to food and drink products (82 per cent in favour).

A majority (65 per cent) said children's cartoon characters and sports stars should be banned from the packaging of unhealthy food and drink, and 60 per cent said there should be a limit to the number of fast food outlets which can be located in any one area.

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However, the researchers noted that while obesity disproportionately affects the most deprived Scots, this group was also the least likely to support legislative measures to curb the problem. This included both measures which would increase the cost of junk food and sugary drinks, such as taxation, as well as policies which had no direct impact on the price of food, such as banning the sponsorship of unhealthy food and drinks at sports events.

A Scottish Government consultation on tackling obesity - due to close on January 31 - has proposed interventions such as outlawing multibuy deals on junk food, confectionary and high-calorie soft drinks.

Deborah Shipton, Public Health Intelligence Advisor at NHS Health Scotland, and author of the report, said the results were encouraging.

She added: “They tell us not only that the public agree that the levels of overweight and obesity in Scotland is a problem, but crucially that they believe that supermarkets, food producers, schools, the media and the government, alongside individuals, all have a role to play to address it.

Read more: See Camley cartoon

“The findings also give us insight into how different groups talk about and understand obesity. We can tailor interventions to get maximum benefit and we can feel confident about some of the bolder, societal level actions needed, safe in the knowledge that the majority of the public understand the need for and support them.

"Taken together with the evidence of what works, today’s report brings us closer to making sure that the places we live, work, play, learn and shop help us make healthy choices and maintain a healthy weight, so that we can improve health, reduce health inequalities across Scotland”.

Lorraine Tulloch, Programme Lead of Obesity Action Scotland said: "It is clear that the majority of the public are in favour of changes to the food environment to make it easier for them to make the healthy choice. People in Scotland recognise the harm that current levels of overweight and obesity are causing and are ready for these much needed changes.”