Study reveals £340 million NHS cost of childhood weight issues – including underweight children
New research from the University of Oxford has revealed that the NHS spends an estimated £340 million each year on healthcare linked to weight-related problems in children – and it is not just obesity that is driving the cost. The study found that underweight children require a similar level of medical support to those who are living with severe obesity, challenging common assumptions about childhood health priorities.
Funded by the National Institute for Health and Care Research (NIHR), the study provides the first national picture of how children’s weight impacts NHS spending. Using electronic health records from more than 268,000 children aged 2–15 across England, the researchers found that around 2.5 million children with unhealthy weight are contributing to rising healthcare costs.
Crucially, the data show that healthcare use increases sharply after a child’s weight is formally recorded in their GP record. This suggests that identifying weight concerns often leads to more medical intervention – but only when appropriate services are available.
Children aged four to five living with severe obesity had the highest additional (‘excess’) healthcare costs at £472 per year.
Girls living with severe obesity incurred higher costs than boys (£253 compared with £138 per year).
Only White children showed consistently higher healthcare costs across all groups with unhealthy weight.
Underweight children had substantially higher healthcare use after weight measurement, while those living with severe obesity had moderately higher use.
Dr Olu Onyimadu, lead author from Oxford’s Nuffield Department of Primary Care Health Sciences, said: “This work suggests we may have been looking at this the wrong way. It’s not just obesity that drives costs. Underweight children may need comparable support and generate similar costs per capita to the NHS. We need to think about the full spectrum of unhealthy weight when planning services.”
The findings come as the government’s 10-year health plan calls for a shift from treatment to prevention. The study provides NHS decision-makers with new evidence to help target resources more effectively.
Professor Stavros Petrou, co-senior author and NIHR Senior Investigator, said: “These numbers give commissioners and practices the evidence they need to make the case for weight-management services. Early intervention across the weight spectrum could generate substantial savings while improving children’s health.”
The study also uncovered ethnic variations, showing that White children consistently had higher excess healthcare costs when living with overweight or obesity compared with other ethnic groups – insights that could help address health inequalities.
Professor Mara Violato, co-senior author based in Oxford Population Health, added: “With 27 per cent of children aged 2–15 living with overweight or obesity, plus those affected by underweight, we are looking at a huge opportunity for preventive care. These detailed cost breakdowns by age and sex can help planners identify which children to prioritise.”
The research highlights that once weight issues are identified, children typically receive more medical support – from nutritional advice to mental health care – reinforcing the importance of regular check-ups.