New Oxford-led research reveals that underweight children require as much NHS support as those with severe obesity, challenging assumptions about childhood health priorities and highlighting the need for services across the entire weight spectrum.
A major study funded by the NIHR ARC Oxford and Thames Valley and supported by Oxford Health BRC has found that childhood weight issues cost the NHS an estimated £340 million each year. Importantly, the research shows that underweight children generate comparable healthcare costs per child as those with severe obesity.
The study, led by Dr Olu Onyimadu, University of Oxford’s Nuffield Department of Primary Care Health Sciences, analysed NHS electronic health records from over 268,000 children aged 2–15 across England. It provides the first national breakdown of healthcare costs linked to children’s weight.
Key findings include:
- Four to five-year-olds with severe obesity had the highest excess costs at £472 per year.
- Girls with severe obesity cost more than boys (£253 vs £138 annually).
- Healthcare use was substantially higher after weight was measured for underweight children, and moderately higher for children with severe obesity.
- Only White children showed clearly higher healthcare costs across all unhealthy weight groups.
Dr Onyimadu 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.”
Implications for NHS Planning
The findings come as the government implements its 10-year health plan, which emphasises prevention. The research offers NHS decision-makers robust evidence to support investment in both prevention and weight-management services in primary care.
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 found ethnic variations in healthcare costs, with white children consistently showing higher excess costs when overweight or obese compared to children from other backgrounds. This insight could help the NHS target support more effectively and address health inequalities.
Professor Mara Violato, co-senior author based in Oxford Population Health, added:
“With 27% 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.”
Practical implications
The research suggests that once a child’s weight issue is identified, the NHS responds with additional support, but this only works if appropriate services exist. The findings strengthen the economic case for investing in both prevention programmes and weight-management services in primary care.
For commissioners and practices developing business cases for new services, the study provides robust, UK-relevant evidence to demonstrate value for money with findings directly applicable to NHS decision-making.
The research team emphasised that these cost estimates can now be used to assess whether specific weight-management programmes offer value for money, helping the NHS make informed decisions about which interventions to fund.
The full study is published in JAMA Network Open
