A major analysis has shown that 11 cancers are becoming more common in young people in England, with the researchers suggesting that artificial ingredients, school uniforms, and frying pans may be partly to blame for the surge in under-50s.
Published in BMJ Oncology, the analysis found that ultra-processed foods, known as UPFs, could be one cause, but that “forever chemicals” used in (non-stick) cookware, clothing and household products, could also shoulder some responsibility, although these factors are likely to be behind only a small proportion of new cases, reports the Daily Mail.
The researchers, from The Institute of Cancer Research and Imperial College London, examined incidence trends across more than 20 cancers in England between 2001 and 2019, before comparing the findings with the latest diagnosis data from 2023.
A full explanation for why levels of the disease are increasing remains elusive, but their findings reveal that a decades-long pattern of people becoming more overweight is also likely to play some role, even though it is far from the whole story, according to the BBC.
Why cancer has been increasing in people's late teens, 20s, 30s and 40s has been puzzling scientists for years, and the team worked through national trends in both cancer and lifestyles in search of a pattern.
They showed that bowel cancer, thyroid, multiple myeloma, liver, kidney, gallbladder, pancreatic, womb lining (or endometrial), mouth, breast and ovarian cancers were all increasing – bowel and breast cancers being the most common in younger adults, with a combined 11 500 cases a year, while pancreatic and gall bladders were much rarer.
Only bowel and ovarian cancers were increasing exclusively in the young, with the other nine increasing in older adults too.
The study also analysed patterns in behaviours already known to increase the risk of cancer.
It showed that smoking levels, alcohol consumption, levels of physical exercise, the amount of red and processed meat and the number of diets low in fibre, were all either getting better or staying the same.
These behaviours all have a role in cancer, but don't explain why cancer has increased. The report said the only data that aligned with the increase in cancer were levels of overweight and obesity, which have escalated since the 1990s.
Extra fat tissue is thought to alter hormones in the body, such as insulin, which can affect the risk of cancer.
However, even this is an imperfect answer, with the experts saying weight gain alone cannot explain the sharp rise in younger adults.
For instance, in bowel cancer, they estimate that for every 100 extra cases, 20 may be due to excess weight while 80 are still unexplained.
The researchers said it was important to prevent all cancers, not just the “extra” ones. It is estimated that nearly 40% of cancers worldwide can be prevented with lifestyle choices like not smoking.
Some 7m cancer deaths a year preventable
“It is very worrying that cancers are increasing in young people,” Professor Montserrat García-Closas, from The Institute of Cancer Research, told the BBC.
The team said that while cancers in young people were increasing, it was important to remember they were still dwarfed by cancers in older age groups.
One in 1 000 young people (aged in their 20s, 30s and 40s) get a cancer diagnosis each year compared with around one in 100 for older age groups (in their 50s, 60s and 70s), they said.
Professor Marc Gunter, co-director of the Cancer Epidemiology and Prevention Research Unit at Imperial College London, said while there has been discussion about ultra-processed foods (which studies suggest now comprise around half of the average UK diet), PFAS, and antibiotic use, “there’s still a lot we don’t know”.
Sweetened drinks, inflammation, air pollution, gut bacteria and weed-killers have all been suggested as triggers.
It is also being investigated whether getting better at detecting cancers is leading to more being diagnosed at a younger age.
Swelling statistics
The study adds to a growing global picture. In the US, early-onset cancer cases rose by almost 15% between 2010 and 2019, with younger adults increasingly being diagnosed with diseases once seen mainly in older age.
They are calling for urgent research into what is driving cancer in younger people – while warning that policymakers must also tackle the obesity epidemic already fuelling many early-age cases.
“Although BMI remains our best clue as to why cancer is on the rise in this age group, much of the increase is still a mystery,” García-Closas told the Daily Mail.
“This tells us that multiple factors, including early-life exposures, may be acting together. Understanding these patterns is essential if we are to identify what is truly driving cancer risk in today’s generation.”
Women take the heat
The reports showed that in 2023 alone, around 31 000 younger adults were diagnosed with cancer, with women accounting for almost two-thirds of cases – largely because of breast cancer.
All but one of the 11, oral cancer being the exception, have long been associated with obesity, reinforcing concerns over Britain’s growing weight crisis.
The rise in oral cancer, meanwhile, remains more puzzling. Rates have climbed by 26% across England in the past decade. Among younger adults, cases have jumped by more than 13% over the same period. Some experts believe falling HPV vaccination uptake may be one factor.
Smoking, alcohol and lack of exercise are known to raise cancer risk, but the researchers said that aside from obesity, many of these classic risk factors are actually becoming less common.
Young adults today, for example, are far less likely to smoke or drink heavily than they were two decades ago.
They also highlight antibiotics as being part of the mystery behind the rise in deadly cancers among adults aged 20 to 49. Use of the bacteria-fighting drugs surged in the 1970s, after the success of penicillin led to a widespread belief that medicine had effectively conquered infectious disease.
At the time, far less was known about the long-term consequences of repeated use.
The scientists believe UPFs, PFAS and antibiotics may all disrupt the gut microbiome – the trillions of bacteria in the digestive system that play a crucial role in health. Disturbing that balance may trigger changes linked to cancer.
“But the changes we’re seeing in cancer incidence, particularly the rates in younger adults, don’t have a single cause or simple answer,” said Gunter,
Study details
Temporal trends in behavioural risk factors for cancers with rising incidence in younger adults: an analysis of population-based data in England
Montserrat Garcia-Closas, Zoey Richards, Reuben Frost, Marc Gunter, Amy Berrington de Gonzalez.
Published in BMJ Oncology on 28 April 2026
Abstract
Objective
To assess whether changes in behavioural risk factors could explain rising cancer incidence in younger adults in England, and to evaluate the extent to which established and suspected risk factors contribute to these trends
Methods and analysis
Cancer incidence data from national registries (2001–2019) for 22 sites in women and 21 in men identified cancers with increasing incidence in adults aged 20–49 years. Trends in smoking, alcohol, diet, body mass index (BMI) and physical inactivity were examined using national health surveys. Annual percentage changes (APCs) quantified trends by age and sex. Population attributable fractions (PAFs) estimated the proportion of cancers attributable to risk factors and disaggregated attributable from non-attributable incidence rates.
Results
Eleven cancer sites (three female-specific) with established behavioural risk factors showed rising incidence in younger adults. Similar trends were observed in older adults, except for colorectal and ovarian cancer, which increased only in younger adults. For some cancers, incidence increased more rapidly in younger than older adults. PAFs for younger adults ranged from 7% to 65% depending on cancer type. All risk factors except obesity showed stable or declining prevalence. For BMI-related cancers, both BMI-attributable and BMI-non-attributable incidence increased, though more slowly for the latter. For example, BMI-attributable colorectal cancer in younger women increased from 0.9 to 1.6 per 100 000 (APC 4.3%), while non-attributable rates rose from 6.4 to 9.6 (APC 3.2%).
Conclusions
Behavioural risk factors account for a substantial share of cancer burden but, apart from BMI, are unlikely to explain the rising incidence in younger adults. The present findings underscore the urgent need to investigate emerging risk factors, while strengthening prevention efforts targeting known factors across all ages.
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