The old adage is true, prevention is better than cure.

For people, preventing illness means a better quality of life. For our healthcare system, it is cheaper and more effective to treat fewer people for fewer problems. For our economy, preventing illness means more people in work; and for our next government, prevention is the only way to turn the tide on population health without blowing the budget. 

But despite advancements in healthcare and medical treatments, the UK is currently failing to prevent illness – our health as a nation is getting worse. 

The IFS reports that, even before the pandemic, the number of people living with a single chronic condition was growing by 4% a year and the number living with multiple chronic conditions was growing by over 8% a year. 

Today, over 20 million people in the UK have a muscular-skeletal condition such as arthritis or back pain, over 5 million have diabetes and more than 3 million people are living with cancer. NHS waiting lists have grown to an all time high of 7.5 million, and long-term sickness is seeing 2.8 million people of working age left economically inactive.

We are becoming a sick nation.

Our healthy life expectancy statistics make for tough reading. Although life expectancy has increased by five years since 1993, the number of years a person can expect to live without illness is decreasing. This means that we are spending longer periods of our lives in ill-health. 

These averages also mask stark and unfair inequalities: you are much more likely to spend additional years in poor health if you live in one of our nation's most deprived areas.

It is only going to get worse…

These statistics are reason enough for concern, but looking forward to 2040, the Health Foundation projections state that nearly 25% more working age adults will have a diagnosed major illness. Beyond the human costs, this will have a devastating impact on labour market participation. 

… and we will not be able to afford to treat everyone

Keeping pace with increasing health needs is already a huge fiscal challenge. If our health needs continue to grow more quickly than our health service provision, we will see an ‘illness gap’ emerge that will grow wider and wider. 

Crudely, the government has three ways to respond to this growing treatment shortfall:

1. Accept the population getting much sicker, and live with the impacts on waitlists and economic inactivity.
2. Accept that we will need to spend much more on treating sickness, with impacts on other areas of government spending or revenue.
3. Stop these trends in their tracks by addressing the drivers of worsening health. 

Political promises currently focus on increasing hospital activity and health system funding to meet treatment needs, with costs to be offset by productivity measures. 

There’s no doubt increasing spending is part of the solution. But the elephant in the room is that, even with increased funding, it will be challenging for the health system to keep up with demand. No manifesto, from any political party, has committed to increasing funding to match projected health spending needs, and even if the NHS can deliver long-run average productivity growth, productivity gains will still be insufficient to offset the fiscal impacts of worsening population health.

By the end of 2023, the UK was spending £211 billion on health services annually. Health spending has grown faster than any other area of public spending since 2000, now accounting for 20% of total government spending, and 8% of GDP – a greater share than ever before, except for during the pandemic.

With the increasing sickness burden driving health spending growth, what will matter for the next government is moving the dial on healthy life expectancy: growing the years spent in good health and reducing the years spent in ill health. That means stopping and reversing current illness trends.  

So, to get a sense of the savings that are on the table, consider the following estimates based on IFS projections and total managed health expenditure:

• If we could stop the growth in chronic conditions over and above population growth - ie, holding prevalence of illness where it is today - we could avoid cumulative health spending growth of almost £500 billion by 2040.
• But even by halving the growth of chronic conditions over and above population growth, we could avoid cumulative health spending growth of around £200 billion by 2040.

A government with ambition doesn’t need to stop there. Many common conditions are reversible and we know how to reverse them. And if we could reduce the current overall prevalence of conditions across the population, rather than just slowing or halting their growth, we could see reductions in cost that could offset other increases in health spending, like new technologies or pay increases. 

Global Burden of Disease projections show that preventable behavioural and metabolic risk accounts for almost all the projected growth in illness in the UK beyond population growth. Although these figures are just projections, they give a sense of the goal posts for a government serious about taking preventative action.

Public health experts talk about three key categories of health prevention: primary, secondary and tertiary. Primary prevention seeks to prevent illness or injury from occurring in the first place. Secondary prevention seeks to reduce the impact of illnesses or injuries by diagnosing and treating them early. Tertiary prevention seeks to manage conditions to prevent long-term deterioration. 

All types of prevention are cost-effective when compared to the ‘worst case’ scenario: significant deterioration in illness resulting in (expensive and invasive) hospital treatment. But some are more cost-effective than others. This is clear when we compare the cost of achieving one additional year of life in perfect health (also known as a quality-adjusted life year or QALY):

Decision makers can maximise health gains within limited budgets by focusing on the most cost-effective interventions. Although a NICE analysis of public health interventions from 2011-16 found that a third of interventions were not cost effective, it also found that two-thirds were cost-effective and a quarter actually saved money compared to current services. Cost-saving interventions included Sure Start, smokefree policies, and regional multi-component diabetes interventions. 

The interventions referenced above are discrete initiatives, usually implemented at a local level, with known resources. Harder to measure are system-level interventions, implemented at a national level, such as regulation and tax. Although these interventions have some small implementation costs, largely they do not rely on additional government spending. 

Despite measurement challenges, available evaluations show these system-level interventions are the most cost effective prevention available. For example, increasing the price of tobacco by 10% (ie, system-level primary prevention) has been found to cost just £130-500 per QALY in high-income countries, compared to the £580-915 cost per QALY of publicly provided nicotine replacement therapies (ie, individually-targeted secondary prevention). Both represent excellent value, but increasing tobacco prices is more cost effective by a factor of five.

UK tobacco policy is a masterclass in successful prevention, deploying a highly effective combination of upstream system changes to the tobacco market through regulation and taxation, changes to choice environments by regulating promotion and placements, and, more recently, through smart individual supports like the Swap to Stop scheme.

Thanks in no small part to the actions of successive governments, smoking rates have halved from 26% in 2000 to under 13% in 2022. Tobacco-related illness has halved as a proportion of total illness since 1990, and we are already seeing tens of thousands fewer deaths annually than if smoking rates had stayed at 2004 levels. According to ASH, this improvement in population health is worth tens of billions in economic value over decades to come. And we can finish what’s been started, unlocking billions in remaining savings, by moving quickly on manifesto promises to phase out smoking for the next generation.

The government could make major inroads on population health by taking decisive action on obesity. Obesity rates have nearly doubled since 1993, with generations born since 1980 three times more likely to be overweight or living with obesity at age 10 than earlier generations. 

The costs of obesity and related conditions are significant: both in terms of individual impacts, and system costs. Frontier Economics estimates the total annual cost of obesity at over £70 billion. Compared to having a healthy weight, a person living with obesity is at greater risk of developing serious medical conditions. They are nine times more likely to develop type 2 diabetes, three times more likely to develop osteoarthritis, and almost three times more likely to develop chronic back pain. 

Type 2 diabetes is of particular concern. An estimated four million people currently live with the condition in the UK at an annual cost to the NHS of over £10 billion.

But the fact that obesity has been lower in the past means we know another reality is possible. And, whilst obesity is a different kind of challenge, our success with tobacco means we know what will be most effective. We can change markets by regulating or taxing foods (or ingredients) that drive obesity. We can alter the environments in which choices are made, for example through promotion and placement; and we can provide individuals with the support they need to maintain healthy habits.

Ultimately, the next government’s success in delivering on long-term health promises - like putting the NHS back on a sustainable footing or narrowing the gap in healthy life expectancy between the richest and poorest areas in England - as well as the longevity of success on short-term promises, like cutting waiting lists - will depend on making significant improvements to health at a population level. 

Picking up and treating illness early (secondary prevention) and managing illness to soften its long-term impact (tertiary prevention) will no doubt be necessary, but, without serious action on primary prevention, it won’t be sufficient. Turning the tide on generational health will require preventing illness from occurring in the first place – and, in truth, there just isn’t the money for taking an alternate route. 

The good news is that there are lots of good ideas and policies, many of which are relatively inexpensive, already sitting on the shelf. We have both consensus on the need to act and confidence in what will shift the dial. System-level action would have a transformative impact – for individuals, households, and the economy. It just requires a government that is bold enough, and committed enough, to prioritise prevention now.

Endnotes

* We take the cost per QALY estimate for the public health grant of £3800. This grant funded both primary and secondary prevention activities. We assume that the grant activities are evenly split between the two. We then take evidence from the US for the relative cost effectiveness of primary and secondary prevention which finds that the cost per QALY of primary prevention is about two thirds of that for secondary prevention. We assume this ratio holds for activities in the public health grant and use this to estimate a figure of the cost effectiveness of primary and secondary prevention separately.