Obesity levels in Scotland are the second highest in the developed world behind the USA, new statistics have revealed.
Obese people in Scotland are 18% more likely to be hospitalised
The figures were published as the Scottish Government announced plans to remove sweets and fizzy drinks from schools.
Under new rules, the amount of chips served in school meals will also be cut and more fruit and vegetables provided.
Children's Minister Adam Ingram said he wanted to change young people's habits.
The figures , released by ISD Scotland, the statistical wing of the NHS, said the "obesity epidemic" in Scotland must be addressed and outlines the extent of the "major public health problem".
The report puts Scotland second bottom in a list of the developed world's most obese nations, with only America faring worse.
Since 1995, obesity in the adult population has increased by 46%.
There have been marked increases in men aged 35 to 64 and in women aged 35 to 44, while one in five children in primary seven were estimated to be obese in 2004/05.
The report said: "These figures provide little evidence that current approaches to obesity are having any impact.
"The increasing levels of obesity are of serious concern given the levels of morbidity and mortality associated with obesity.
"It is estimated that obese people in Scotland are 18% more likely to be hospitalised than those of normal weight."
The cost of treating obesity-related disease in Scotland was estimated at £171m in 2001.
The prevalence of the condition in Scotland is among the highest of all Organisation for Economic Co-operation and Development (OECD) countries - above the UK as a whole, Mexico, Canada and Australia.
The condition is likely to result in rising levels of Type 2 diabetes, colon cancer and hypertension.
Declining levels of physical activity and "sedentary lifestyles" are highlighted in the report as a possible factor in the growing levels of obesity in developed countries.
The availability of cheap, energy-dense food could be a further factor.
Chips will only be served in schools as part of a nutritional meal
Meanwhile, ministers set out new nutritional guidelines for Scottish schools which will be written in to legislation and be applied from August 2008.
It comes in response to recommendations from a group of nutrition, child health, dental and education experts.
At least two portions of fruit and vegetables will be served every lunchtime, oily fish will be served once every three weeks, while deep fried food will be limited to three items a week.
Sweets and fizzy drinks will be removed from schools and chips will only be served up as part of an overall balanced and nutritional meal.
Mr Ingram said: "By targeting our youngest citizens we can make a lasting difference.
"Putting healthy options on a plate for pupils every day will develop their taste for the food that's good for them and stop unhealthy habits from taking hold."
Tory health spokeswoman Mary Scanlon said the findings of the obesity report were "horrific".
"This sends a clear message that we need to start educating people about the dangers of an unhealthy lifestyle, starting with mothers in ante-natal classes," she said.
In 2003, the Hungry for Success initiative was launched to change eating habits but since then the number of children taking school meals has dropped.