So-called lifestyle illnesses caused by smoking, drinking and obesity are costing the NHS more than £11 billion a year.
According to Public Health England (PHE), preventable illnesses such as diabetes and bronchitis are becoming an 'untreatable epidemic'.
"When you look back to Victorian times, we worried about things like diphtheria and polio, and we've actually managed to conquer those now. The new threats are things like diabetes and chronic bronchitis. They could overwhelm us," Dr Rebecca Wagstaff of PHE tells the BBC.
"They are illnesses for which there is no cure, and they cost the NHS more than £11 billion each year. That's a phenomenal amount of money and more than that, it is taking years off people's lives."
Already, as many as four in ten middle-aged people suffer from a long-term condition with no cure. These include type 2 diabetes, cancer, lung and heart disease, and are often caused by an unhealthy lifestyle.
For the fifth year in a row, PHE is encouraging smokers to quit next month as part of Stoptober.
"Alongside unhealthy diet, smoking is the biggest cause of preventable early death in England, accounting for over 78,000 deaths a year," says professor Kevin Fenton, national director of health and wellbeing for PHE.
"Quitters will soon see they have reduced blood pressure, easier breathing and better circulation. Stopping smoking is the best thing a smoker can do to improve their health."
In fact, though, people quitting smoking could actually put more strain on the NHS.
According to the FullFact fact checking agency, smokers contribute about £12 billion in direct tax revenues to the Treasury every year - far more than the £3-£6 billion cost of treating them.
And, it points out, "In the longer term the total cost might be lower, since some of those who die prematurely due to smoking might otherwise have gone on to cost the service even more money due to other health conditions."
Similarly, the right-wing think-tank the Institute of Economic Affairs concluded last year that while the direct costs of alcohol use – including medical treatment, police, criminal justice and welfare costs – amount to just under £4 billion each year, revenues from alcohol taxes amount to over £10 billion.
"It is time to stop pretending that drinkers are a burden on taxpayers," says author Christopher Snowdon.
The news could fuel calls for a stricter sugar tax to make sure that the obese start paying their way too. Campaigners are unhappy that it will apply only to sugary drinks - and not even to all of those.
It's expected to raise around £285 million, which will be invested in promoting exercise in schools.