Children from poorer backgrounds are more likely to be overweight or obese from pre-school age onwards, researchers at Trinity College Dublin (TCD) have found.

They carried out a study which followed over 41,000 children from childhood through to adolescence in three European countries - Ireland, the UK and Portugal.

The children's body mass index (BMI) was measured and their socio-economic position was assessed based on their mother's education levels

The researchers found no differences in the children's BMI up to pre-school age, however differences began to emerge in the pre-school years (3-5 years).

Children whose mothers had attained only primary or secondary school education gained weight at a faster rate than those whose mothers had gone on to third level education.

Furthermore, these differences continued to widen as the children got older in all three countries.

"This study shows that children from disadvantaged socio-economic backgrounds gain body mass more quickly than their more advantaged peers, are more likely to be overweight or obese from pre-school age onwards, and are more likely to become obese if previously non-overweight. They are quite literally carrying a heavier burden of disease from much earlier in life," commented the study's lead author, Dr Cathal McCrory, of TCD.

He said that the findings reinforce the need to tackle childhood obesity at an early age ‘as these patterns are difficult to change once they have become entrenched'.

"Urgent Government action is now required to understand the material, social, and structural barriers that contribute to these stark socio-economic differences in obesity risk," Dr McCrory added.

Meanwhile, according to the study's senior author, Prof Richard Layte of TCD, the findings show that inequalities relating to health and life expectancy ‘are well established by age five'.

"Most children who are obese have a higher risk of being obese in adulthood with long-term health consequences. This is a public health issue that needs urgent action," he said.

Details of these findings are published in the journal, Paediatric and Perinatal Epidemiology.