WHEN you hear the word sugar, do you wrinkle your nose in disgust and reach for another marinated olive, or think longingly, as I do, of candy floss and toffees?

I would be licking my lips, if I weren't already running a guilty tongue over a graveyard of fillings, thanks to a sweet tooth shared with almost everyone in my school class. The sugar bath millions like me inflicted on our teeth is horrifying - as are Scotland's figures for dental health. Apparently, our children's teeth rank as low today as those in Kazakhstan for cavities and decay.

But our gnashers are merely base camp for sugar and its evil effect on our body. Figures on obesity for Scottish adults and children show that 30% of under 15s are obese. No children in Europe consume more sugar than Scots, and one needn't look far for the cause. For generations, it has been our comfort and joy, whether stirred into tea, shaped into pacifiers for babies, or poured into sweeties, cakes and puddings. I used to smile when I passed an olde worlde sweet shop in Edinburgh that boasted of selling "boilings for connoisseurs". Now I realise it's no laughing matter.

Last week Shona Robison, Minister for Public Health and Sport, admitted the number of obese adults - almost 28% - is even worse than we'd thought. Only Mexicans and Americans carry more flab. And yet, health care workers in schools are not allowed to mention the word "fat" when suggesting parents need to improve their chubby child's diet.

For years, fats were seen as the enemy, hence the rise of a low-fat industry whose products were so tasteless a generous sprinkling of sugar was added to give them flavour. The most popular sweetener was what's called by one doctor "the Voldemort of sugars", namely high-fructose corn syrup. Sweeter and cheaper than natural sugars, it is found in countless foods, but nowhere more perniciously than in soft drinks.

Since the west's fat consumption has fallen in recent years, but our weight has not, research has shown that it may well be sugar that is to blame.

Some scientists dispute this, claiming a calorie is a calorie wherever it's found, but increasingly the malign effect of sugar on our metabolism is being brought to light.

According to Dr Robert Lustig, author of Fat Chance: The Bitter Truth about Sugar, "fructose can fry your liver and cause all the same diseases as alcohol". Fructose is a natural ingredient in fruit but it can also be dangerous we're told, not least because, according to Lustig, it can turn off the switch that tells us we have eaten enough.

Suddenly, Scotland's centuries-old love of sugar takes on a sinister complexion. What seemed a peccadillo, a national predilection far less serious than our love of the deep fat frier or the so-called amber nectar, is shown as unhealthy, irresponsible, and potentially toxic. A surfeit of sugar is now being held directly responsible for the rise in diabetes in younger people, and for many cases of high blood pressure, heart and pulmonary disease. Soon it may even overtake tobacco for its ill effect on the heart.

There is something nightmarish about this discovery, as if a child's innocent toy has turned into a weapon of mass destruction. Given the levels of ill-health linked to sugar, and the implications these hold for the country's well-being and finances, we urgently need public education programmes to inform people of the dangers of sugar: to tell them that a can of juice is like a grenade, a packet of sweets a time-bomb.

As politicians will be all too aware, changing attitudes won't be easy. New York mayor Michael Bloomberg for instance, is locked in battle with sugar lovers as he tries to ban oversize helpings of sweetened drinks. Yet in France, raising the tax on sugary drinks has already had an appreciable effect on public health, and other countries have followed suit.

We should join them. High on the world's league table of sugar addicts, we ought also to be at the forefront of curbing the country's appetite. Of course, no-one can deny that state interference will be as unpopular as snatching sweets from a baby. There's little doubt, though, that in the long run it will make everyone's life a great deal sweeter.