Women under the age of fifty who regularly consume ultra-processed foods face a significantly heightened risk of developing bowel polyps, which are directly linked to cancer, according to concerning new research published today.
The Alarming Study Findings
The comprehensive global analysis discovered that colon cancer stands as the only form of the disease experiencing a dramatic surge exclusively within this younger age demographic. This worrying trend has prompted researchers to investigate potential environmental triggers more closely, with diet emerging as a primary focus.
While ultra-processed foods have long been associated with bowel cancer due to their typically low fibre content and high levels of emulsifiers, data specifically examining the connection between UPFs and early-onset bowel growths had been largely overlooked until now.
Research Methodology and Participant Details
In this landmark study, leading cancer experts from the PROSPECT team – funded by Cancer Grand Challenges, a global research initiative founded by Cancer Research UK and the National Cancer Institute – meticulously analysed endoscopy results from over 29,100 female nurses aged between 25 and 42.
These participants were enrolled in the Nurses' Health Study II, providing researchers with valuable early insights into diet-related cancer progression. The investigation, published in the prestigious journal JAMA Oncology, specifically examined whether increased UPF consumption was associated with higher risks of non-cancerous tumours and serrated lesions in the bowel – the two main drivers of colorectal cancers.
The researchers made a startling discovery: women who consumed the highest amounts of ultra-processed foods demonstrated a 45 per cent increased risk of developing growths on their large intestine or rectum. Although polyps are usually harmless and not always concerning, in a small percentage of cases they can become cancerous over time.
Lifestyle Factors and Long-Term Implications
Dr Andrew Chan, an expert in clinical and translational epidemiology at Massachusetts General Hospital and the study's lead author, commented: 'We're seeing more cases of bowel cancer in younger adults and we still don't understand why. Our research is exploring possible factors such as diet, lack of exercise and disruption to the gut microbiome, which may all play a role.'
The research team collected comprehensive data through questionnaires sent every other year starting from 1989, covering lifestyle factors, family and medical history. Dietary habits were tracked through food frequency questionnaires conducted every four years beginning in 1991.
Over the 24-year study period, researchers found that participants who consumed the most UPFs generally had higher BMI, smoked more frequently, and had a greater prevalence of type 2 diabetes compared to those who ate less processed food. These women also tended to take more anti-inflammatory painkillers like aspirin, were more likely to be on hormone replacement therapy, took fewer supplements, and were less physically active than their peers.
On average, UPF intake constituted approximately 35 per cent of total daily calories among the study participants – equating to around 5.7 servings daily, primarily from breads and breakfast foods, sauces, spreads, condiments and sugary drinks.
By the study's conclusion on 1 June 2015, when all participants had reached age fifty, researchers had recorded 1,189 cases of early-onset tumours and 1,598 serrated lesions. Those consuming the most UPFs were significantly more likely to develop early-onset tumours, though not lesions, with artificially sweetened beverages identified as a key driver of this trend.
Broader Implications and Public Health Recommendations
The researchers concluded: 'This suggests the combined exposure to multiple food additives may exert a cocktail effect on gut health by impairing barrier function and altering the microbiome. Our findings highlight the importance of diet in early-onset colorectal carcinogenesis and support dietary quality improvements as a strategy to mitigate the increasing burden of early-onset colorectal cancers.'
Professor Charles Swanton, Cancer Grand Challenges Scientific Committee Chair and Cancer Research UK’s Chief Clinician, added: 'This study sheds light on how diet and other factors are associated with gut health and changes in the bowel linked to cancer risk. While causation has not yet been demonstrated, researchers around the world in the PROSPECT team are combining large-scale population studies with cutting-edge lab science to build a clearer picture of the factors that may be contributing to this trend.'
The context of this research is particularly alarming given current statistics. Bowel cancer remains the fourth most common cancer in both the UK and US, with approximately 44,000 annual cases in the UK and 142,000 in the US. Previous research indicates that in England, diagnoses among 25 to 49-year-olds have increased by more than 50 per cent since the early 1990s.
Meanwhile, in the United States, projections indicate the disease will become the most common cancer in people under 50 by 2030. Cancer Research UK estimates that over half (54 per cent) of bowel cancer cases in the UK are preventable, highlighting the crucial role of lifestyle factors.
Fiona Osgun, head of health information at Cancer Research UK, emphasised: 'Whilst this study doesn't directly measure cancer risk, it offers useful insight into how diet might influence early changes in the bowel that sometimes lead to cancer. Our diets are shaped by the world around us, from food prices, marketing and local availability. This can make healthy choices harder. We need broader changes – from food policy to public health initiatives – to make healthier diets more accessible for everyone.'
Common symptoms of bowel cancer include persistent changes in bowel habits, blood in stool, abdominal pain, unexplained weight loss and fatigue. The charity strongly advises anyone experiencing these symptoms to contact their GP for professional advice.
