Big kids are getting too big

Researchers led by The University of Manchester say that faster-growing children might be especially vulnerable to the fattening effects of the ‘obesogenic environment,’ that is causing society to get fatter.

Lead researcher Dr Iain Buchan, Director and Senior Lecturer in Public Health Informatics at the Northwest Institute for Bio-Health Informatics at Manchester said: “Our study shows that the UK needs to change its eating and exercise habits. The more children eat, the more they show the effects of what we are offering them – basically far too much unhealthy food and far too little chance to exercise.

“The largest increase in body mass index (BMI) in our study occurred in the tallest children, while that for the smallest hardly changed. Tall stature has therefore become important for child obesity. It shows a drive to adiposity (fatness) in young children involving both growth and appetite, with fast-growing and hungrier children more exposed to the obesogenic environment.”

The team, which also includes Great Ormond Street Hospital’s Institute of Child Health and The University of Liverpool, surveyed the weights of 50,000 three-year-olds from the Wirral (where BMI has been rising for 16 years) from 1988 to 2003.

They found that mean BMI rose by 0.7 kg/m2 while mean height fell by 0.5cm. Over the same period the weight-height correlation rose from 0.59 to 0.71 as the BMI of taller children rose.

Among the shortest 10% of the children mean BMI rose by 0.12 kg/m2, as against 1.38 kg/m2 among the tallest 10% – a 12-fold difference. Adjustment for age, sex, birth-weight, seasonality and deprivation did not alter their findings.

Dr Buchan added: “We have shown a strong relationship between child growth and obesity. The next research challenge is to work out exactly how this happens.

“We are looking at some deeper relationships between child growth and obesity with the data we have. Beyond this new data are required.

“One area in particular that needs more study is very early feeding. Animal studies show that obesity might be prevented permanently by reducing the amount of calories consumed by young in the first few weeks of life – exploring whether or not this is a safe and effective approach to preventing obesity in humans needs careful research.”