Wherever the us goes, as the old cliché states, the UK is sure to follow. So perhaps it has not come as much of a surprise that the first white children in Britain have been diagnosed with Type II diabetes, reflecting a similar pattern in America.

The age group and ethnicity are the factors that make this development so significant. Type I diabetes is most commonly a childhood disorder and Type II diabetes has occasionally been found amongst black and Asian children - an ethnic group which does appear to have a genetic propensity to the condition. This is why Type II is generally referred to as "adult onset" diabetes.

The key to understanding why three girls and one boy aged from 13-15 have suddenly appeared susceptible to this condition - and why we should all care - appears to be obesity.

The four children had body mass indexes - where anything over 30 is classified as obese - of 40.6, 39, 36.9 and 32.66 respectively.

The statistics bear it out for themselves - and everyday experience tells us that many more children have problems with their weight than 10 years ago. Would it be wrong, however genuine the intention, to recall that in my class at school there was one boy commonly referred to as "fatty" because, actually, his unique feature was that he was the only overweight child in a class of 30?

A National Audit Office report finding last year that a third of 15 year olds were overweight was confirmed by a British Medical Journal study which reported a "startling increase" in the proportion of overweight children between 1984 and 1994 - from five per cent to nine per cent in one decade.

One in three children of this age group are now said to have a similar problem with their weight. And as the new diagnoses of Type II diabetes show, the long term consequences for these children goes way beyond just an issue with self-esteem in a society which often appears to value thinness above educational achievement.

There is also a close biological relationship between obesity and such conditions as hypertension, arthritis, cardiovascular (CVD) and gallbladder disease, and respiratory complications such as pulmonary hypertension and right heart failure. Excess calorie intake and a high-fat diet have also been implicated as a crucial factor in cervical, ovarian and gallbladder cancers in women and colorectal and prostate cancers in men. So serious are the health implications of excess body weight, that the psychologists Brownell and Wadden stated in 1992 that: "It must be realised that diabetes mellitus, hypertension, dyslipidemia [a decrease in circulating lipids implicated in heart disease], CVD and stroke are aside from cancer, Aids, and violence, the leading causes of morbidity in the developed world"If obesity could be prevented, a very significant and positive impact on chronic disease and mortality would occur."

Social stigma is a very real experience for the obese: when, as long ago as 1969 a group of students was asked to rate their peers for popularity and personal characteristics, 86 per cent described their overweight counterparts as "lazy", 90 per cent as "weak" and 94 per cent as "stupid".

For most of us adults, fighting "middle-age spread" - particularly after having several children - is generally considered an almost inevitable part of our getting older. But what explains the reason why our children are getting fatter?

Many of us subscribe to the view that genetics play a part in weight and whilst indeed they do when it comes to our shape, twin studies have actually shown a stronger heritable relationship amongst the slim.

So whilst there is some evidence for the role of genes there is also popular confusion over the difference between a "proven link" and a "relationship": is a low metabolic rate, for instance, a cause or a consequence of obesity? It is true that if one parent is obese the chance of having an obese child is 40 per cent, rising to 80 per cent if both parents are overweight. But research into socio-economic status (SES) and modelling - poorly learned food choices - may go some way to explaining this.

For instance studies have shown that women with a higher SES are more likely to be better informed as to what constitutes healthy eating and have more leisure time in which to exercise to boot. SES of the parent is also one of the best predictors of the SES of a child and appears to have a worrying impact on diet - demonstrated in a 1986 study, which found that children of a low SES eat up to 500 more calories a day, and a National Diet and Nutrition Survey in 2000, which found that children from the lowest socio-economic groups actually had a lower intake of fat but also the lowest intakes of vitamins and minerals.

And across all social groups, the same week-long survey found that whilst 80 per cent of children ate white bread, chips and biscuits, just 40 per cent eat cooked green vegetables, with only 47 per cent of boys and 57 per cent of girls eating any raw and salad vegetables. Seventy-five per cent chose to drink soft (carbonated) drinks rather than juice or water. A horrifying one in five eat no fruit at all.

The government's Social Exclusion Unit report in 2000, highlighting the dearth of local shops selling fresh fruit and vegetables on run-down and low income housing estates, spurred Health Minister Yvette Cooper into action in 2000. Stating that the government needed to ensure that "fruit and vegetables are accessible for everyone", Cooper introduced a school programme to issue a piece of free fruit a day to all four to six year olds.

There has been a revolution in our eating habits in the developed world - the percentage of calories consumed from fat has increased from 32 to 43 per cent since 1910. We eat out far more frequently than we did even a decade ago. Fast food is full of hidden fats and sugar but many of us are ignorant as to which are the worst culprits. A Health Which? report last year into takeaway food found what it described as a "staggering 60g of fat and 44g of sugar" in one portion of battered sweet and sour pork with egg fried rice. A chicken tikka masala with pilau rice was found to contain 47g of fat and a lamb passanda with pilar rice had 990 more calories than a Burger King Double Whopper with cheese. To put this more in context, the average recommended daily fat intake for a male adult is 95g of fat and 70g for adult women.

There is a general conception that obese children just eat more but whilst there is some evidence for this the reasons for this behaviour are complex. Targeted by companies which market their food especially at children, perhaps obese children are just over-responsive to external cues such as packaging and image, taste and smell rather than an internal cue such as hunger or satiety?

But the stereotype that fat people are simply more "greedy" is complicated by the huge variations in the amount people eat - often without gaining any weight. Whilst acknowledging that a greater degree of our calories now originate from fat (compared to carbohydrate), the co-director of the Human Nutrition Research Centre at Newcastle's Royal Victoria Infirmary, Professor Andrew-Rugg-Gunn, pointed to the fact that from a vitamin intake perspective, many children's diets had in fact improved. It was their "energy-output" that had decreased. "In short they are not doing as much exercise as they should," he said.

Certainly modern technology has increased sedentary habits. Just having a telephone extension saves us an estimated mile of walking in the course of one year - the equivalent of 2-3lb of fat or 10,500 kcals. It doesn't take any stretch of the imagination to visualise the impact, on the life of a modern day child, of TV remote controls and the school run. But these labour saving modern conveniences are obviously only a fraction of the picture. To this we must add the far more significant sociological "couch-potato" lifestyle changes encouraged by modern technology such as Playstations and videos - not to mention less physical education classes and the selling off of recreation grounds by schools desperate to raise funds. Last year's NAO report found that whilst three-quarters of 11-16 year olds spent more than two hours a day watching television, only one third took part in PE for more than two hours a week.

Overweight children do appear to behave differently compared with their slimmer counterparts. In the USA time-lapse photography was used to observe obese and non-obese children. When swimming obese girls were found to spent more time floating and, when playing tennis, were inactive 77 per cent of the time compared with 56 per cent for non-obese girls.

But it would be wrong to draw the conclusion that these studies corroborate the second stereotype that fat people are just "lazy". The relationship is much more complex than that - as the Journal of New England Medicine speculated, perhaps "a sedentary lifestyle is both a cause and consequence of obesity". Lack of exercise may not necessarily be the cause of obesity - but rather a consequence of social stigma. This may go a long way in explaining why it is often so difficult to lose weight - and play a large part in maintaining it.

As much as popular psychology books and newspaper "seven-day" diets would like us to believe, obesity cannot be explained by a single cause. It is the result of a complex cocktail of behaviour, genetics and socio-economic status.

Unlike Type I, Type II diabetes can - though by no means always - be regulated through careful eating habits and exercise. However for some people this will not be enough and they will have to take insulin for the rest of their lives in order to avoid serious complications.

The government's free fruit scheme may well have doubled many children's fruit intake but a lot more needs to be done in both promoting physical activity and healthier food choices. Fast food advertisements are regularly targeted at children and the poor labelling of so-called "low-fat" supermarket foods - which are often just the same in their fat and calorie content - do not help concerned parents to make an informed decision.

"These cases confirm a very worrying trend," said the Head of Care Developments at Diabetes UK, Simon O'Neill, in the wake of the finding of Type II cases in white children. "Our children need more exercise and a healthier diet. Unless we take action now we will follow the American example and create a new group of people at risk of diabetes. The potential long term impact of this is frightening, both in terms of the impact on the children and the cost of dealing with it."

Diabetes is divided into two distinct types: I and II

Type 1

Normally only seen in children, this category of diabetes is believed to be an auto-immune disease whereby the cells in the pancreas responsible for producing the hormone insulin have been destroyed. Without sufficient levels of the hormone the body is unable to absorb glucose into the body's cells. This category of diabetes is commonly referred to as "insulin dependent" as the sufferers have to regularly inject themselves with the hormone between two and four times daily.

Type II (commonly referred to as"adult onset" or "non-insulin dependent")

This category is normally only seen in people over 40 years-old, whose fat and muscle cells have either lost their sensitivity to insulin and/or whose pancreas is not producing sufficient insulin to overcome the resistance to the action of insulin in the body's cells. Whilst genes contribute to the susceptibility to this type of diabetes, it is mainly believed to be triggered by a combination of obesity and a sedentary lifestyle. The appellation "non-insulin dependent" is misleading as some people with Type II will need to inject insulin in order to stay healthy.

High Risk Groups

Symptoms

Complications