To better understand the wider economic impacts of weight loss medications, Nesta partnered with Oviva to analyse real-world data from around 2,000 NHS patients living with obesity who took part in a digital weight management programme including semaglutide.
Obesity costs the UK an estimated £107 billion a year, including around £24 billion in productivity losses and £9 billion in NHS costs. While new weight loss medications such as semaglutide and tirzepatide have shown strong clinical results, there is still limited evidence on their wider economic benefits in the UK.
NHS England plans to roll out tirzepatide to 1.6 million people over 12 years – around 9% of adults currently living with obesity. Understanding the broader economic impact of these treatments could help inform decisions about the scale and pace of access through the NHS.
This analysis explored how participation in Oviva’s programme affected weight loss, sickness absence, employment and healthcare use over a 12-month period.
What’s in the report
The report examines the potential economic benefits associated with weight loss medications and digital behavioural support.
The analysis found that:
- participants experienced an average 17% reduction in body weight over 12 months, consistent with findings from clinical trials of semaglutide
- sickness absence fell by around 30%, from an average of 1.3 days over three months at baseline to 0.9 days 12 months later
- when scaled to the NHS’s planned rollout of tirzepatide, the reduction in sickness absence could translate into productivity gains of £150-300 million
- participants reported lower frequency of GP and hospital appointments after 12 months
- across the study population, healthcare appointments fell by 42%.
Findings and implications
The findings suggest that weight loss medications could deliver important economic benefits alongside improved health outcomes.
The key takeaway for national policy is that measurable economic gains, particularly through decreased workplace absenteeism, can offset some of the cost of these treatments. By broadening the focus beyond weight loss to include these wider socioeconomic returns, policymakers have the opportunity to strengthen the investment case within timelines that align with the government's growth mission.
Currently, only ~9% of people living with obesity will have access to these medications under the NHS over 12 years, so there is a huge gap in access for those with the highest clinical need. These results strengthen the case to deliver on existing commitments, increase the scale and pace of the rollout to ensure equitable access and regularly re-evaluate the cost-effectiveness as more evidence emerges.
Combining effective obesity treatment with stronger prevention policies offers the best opportunity to improve health, reduce inequalities and support long-term economic growth. Weight loss medications alone will not solve the obesity crisis. Nesta’s research shows that improving the food environment remains the most effective long-term approach to reducing obesity. Policies that make healthier food more available, accessible and affordable - such as a Healthy Food Standard for large food businesses - remain essential alongside expanded access to treatment.
Nesta was fully independent as a charity and received no funds from Oviva; we partnered on a mutually beneficial basis to further our respective aims.
