In the last 30 years, obesity rates in England have doubled. Yet, over that same time period we've seen almost 700 initiatives fall short of tackling the problem. That's where Nesta's blueprint for halving obesity comes in.

The blueprint, first published in November 2024, is designed to finally turn the tide on obesity by guiding policy in the most effective direction. As the most comprehensive cost and impact assessment of obesity policies to date, Nesta's blueprint makes it possible to identify which solutions to pursue and at what scale. We've even collated four policy packages so policymakers can see which policies are complementary - and offer the greatest value for money while meeting the impact goal of halving obesity prevalence.

At its core, the blueprint takes rigorous academic analysis and transforms it into actionable policy advice. That’s a gift for those of us (like me), who have come from academia and want to turn robust evidence into real-world impact. To that end, we have recently updated the blueprint to reflect the most recent, best-quality policy evidence. Here are six things we learned:

Nesta’s preferred approach remains one of prevention and treatment, which includes regulation that incentivises food businesses to improve the health of what they promote, advertise and sell. Our health targets for supermarkets proposal will make the biggest impact here, reducing obesity prevalence by around a fifth.

Alongside these preventative measures, we also recommend that access to weight-loss treatment should be expanded for people who need it. As a combination, these measures are high impact, well-evidenced and relatively low-cost.

The evidence is still clear that policies focused on education, information provision, physical activity or voluntary measures are insufficient for meeting the scale of obesity. These policies could still form small parts of a wider strategy, but will not meaningfully shift the dial alone.

In fact, the modelled impact of front-of-pack labelling on obesity has more than halved from 7% to 3% according to our updated analysis based on new research conducted in real-world field settings, instead of laboratory settings. Our new modelling also reflects the additional impact of labelling those packaged products that do not currently carry voluntary front-of-pack labelling in the UK.

The planned NHS England rollout of the weight-loss medication tirzepatide (Mounjaro), based on NICE guidance, will provide a huge benefit to those who need it. However, this won’t make a sizable dent on national obesity rates, as within the time period of our modelling, the treatment will be targeted at individuals living with obesity class 3 (BMI ≥ 40) and multiple comorbidities.

The data shows that tirzepatide will not shift these individuals entirely out of the obesity category; instead, they will move from class 3 to a milder form of obesity (reducing obesity class 3 by 19%). This still carries significant health benefits for those individuals, but highlights that within the current reach of the rollout, these drugs alone will not reduce obesity rates.

Ultimately, the most effective approach to GLP-1 treatment will ensure that all patients who need these drugs can access them safely, promptly and with the right support. We support the focus of the current rollout on those with the highest need. However, we would welcome measures to expand access beyond those with the highest levels of BMI.

We also looked at the impact of the NHS Digital Weight Management Programme. As a less intensive behavioural weight-management programme (BWMP) than earlier forms we have modelled, the programme is likely to be cost-effective. We welcomed its inclusion in the 10 Year Health Plan but our analysis suggests that the proposed expansion will not be sufficient to substantially change national obesity rates, with an estimated reduction of just ~1%.

Minimum unit pricing (MUP) for alcoholic drinks has been implemented in both Scotland and Wales, so we updated the blueprint to model the impact on obesity if England were to introduce this policy as well.

The results show MUP would only marginally reduce population obesity (~1%). But, its wider benefits for physical, mental health and other social issues make it a valuable policy for advancing the government's health goals.

Finally, we welcome the government’s plans to set health targets for food businesses in the 10 Year Plan Health Plan, based on Nesta’s proposal. While mandatory data reporting on the healthiness of food sales is a fundamental prerequisite to targets - the policy can’t stop here.

Our blueprint estimates that reporting on its own would have virtually no impact on obesity prevalence. Setting mandatory targets to improve the health of what is sold is what will drive impact.

It is now critical that the government effectively implements the most impactful policies to realise their full potential.

The blueprint’s standout recommendation - health targets for supermarkets - could reduce obesity by around a fifth. By setting in place this world-first policy, the UK would demonstrate that it is actively learning from past approaches and setting the stage for a healthier future for all.

Explore all updates to Nesta’s blueprint for halving obesity.