According to Steven Blair, an American professor of public health, Scotland is in danger of sleepwalking into obesity.

The truth is that, on this major challenge to public health, Scots have already spent many years with their eyes closed.

The statistics on the subject are clear. According to the most recent official figures, published in November, more than one-quarter of adults in Scotland are obese. Obesity in children is also at alarming levels, with around one in six boys between two and four-years-old classed as obese. But who needs figures? Walk down any high street in Scotland if you want to see the scale of the country's weight problem.

Loading article content

Professor Blair, who quite rightly points out that Scotland is not far behind the United States on this issue, suggests the answer is a change in cultural norms and a much greater emphasis on increasing physical activity rather than eating less. "In simple terms," he says, "we are talking about changing the mindset from thinking 'I must go on a diet' to 'I must become more active'."

Not only is this good advice, the professor's wise words also come just a few days after Scotland's outgoing chief medical officer Sir Harry Burns said something similar. Lack of exercise, he warned, is as damaging to our health as smoking, alcohol abuse and diabetes combined.

If we accept what two such esteemed expert witnesses are saying, the next question is: how can we bring about such a change from a culture based on diets to a culture based on healthy eating and exercise? One of Sir Harry's suggested solutions is that GPs and nurses should be telling their patients which forms of exercise are best, but Professor Blair would go further. He suggests that patients could be prescribed exercise in the way they are prescribed drugs.

It is an interesting idea, although the obvious problem is that no-one can be forced to exercise and GPs would require more support and incentives if the idea is to work. It may be that the idea could form a small part of the bigger solution to obesity, which has to focus much more on prevention than cure. Already, the NHS is creaking under the strain of treating obese Scots and spends millions of pounds a year on prescribing drugs to patients struggling with their weight. It cannot go on treating the symptoms of a growing problem without concerted, radical efforts to tackle the causes.

To its credit, the Scottish Government already has an action plan on obesity and it focuses on many of the right areas, the most important of which is education and advice, in particular education for parents on a healthy diet and regular exercise for their children.

In time, such a strategy - delivered by health visitors, doctors, nurses and teachers - has the best potential to tackle Scotland's obesity problem by forming good habits that persist into adulthood. In addition, it could create a bigger demand for cheaper, nutritious food and help reverse the frightening game Scotland has been playing on obesity: a game of catch-up with the US.