Children from lower social classes up to 5kg heavier than their more advantaged peers

Disadvantaged children born at the start of the 21st century weighed up to 5kg more in their childhood and early teenage years than those from more privileged backgrounds, a new study has found.

Yet in previous generations lower social class was associated with lower childhood and adolescent weight. As a result of these changes, social class inequalities in obesity emerged and widened at the end of the last century.

In 1973, Britain’s most disadvantaged teenagers weighed an average of 1.3kg less than their most advantaged peers. However, by 2015, teens from the most disadvantaged backgrounds weighed an average of 2.4kg more than the most privileged.

The findings, published in The Lancet Public Health suggest that Britain’s obesity epidemic has had a much greater impact on the country’s less well off.

Funded by CLOSER, researchers from UCL compared the childhood and adolescent social class, weight, height and BMI of British children from four different generations for the first time.

Their findings revealed that for children born in 1946, 1958 and 1970 their social class made little difference to their BMI at ages 7 or 11. However, for the children born in 2001, there were socioeconomic inequalities: those with from a lower social class were more likely to have a higher BMI and that the higher the BMI, the wider this socioeconomic inequality was.

The authors say that these trends highlight the powerful influence that an environment encouraging consumption of a high-calorie diet and discouraging physical activity has had on socioeconomically disadvantaged children.

“Our findings illustrate a need for new effective policies to reduce obesity and its socioeconomic inequality in children in the UK – previous policies have not been adequate, and existing policies are unlikely to be either,” says lead author Dr David Bann, of the Centre for Longitudinal Studies at the UCL Institute of Education.

“Without effective interventions, childhood BMI inequalities are likely to widen further throughout adulthood, leading to decades of adverse health and economic consequences.”

David added, “Our results illustrate a need for strong additional legislative changes that focus on societal factors and the food industry, rather than individuals or families. Bold action is needed, such as creating further incentives for food manufacturers to reduce sugar and fat content in food and drinks, reduce the advertising of unhealthy foods to children and families, and incentivise the sale of healthier alternatives. The Soft Drinks Industrial Levy is a positive but likely very limited step in the right direction.”