UK Launches Massive Study into Rising Bowel Cancer Rates Among Young Adults

A large-scale study is recruiting more than 250,000 volunteers across the United Kingdom to investigate the perplexing increase in bowel cancer diagnoses among individuals under 50. The disease, historically more common in older populations, is now being diagnosed at younger ages with alarming frequency.

Experts note that early-onset bowel cancer rates have risen substantially worldwide since 1990, with the UK experiencing particularly rapid increases. While the exact causes remain unclear, obesity is considered a potential contributing factor. Researchers at King's College London, in collaboration with the health science company Zoe, aim to gather extensive data on diet, lifestyle, and environmental influences.

The study, named Prospect-UK, will involve participants aged 18 and over completing online questionnaires detailing their eating habits, lifestyle choices, environmental exposures, and health status. To enable researchers to track cancer development, participants will also consent to linking their information with electronic health records.

A subset of volunteers will be asked to maintain detailed diet diaries and provide biological samples, including blood and stool. Professor Sarah Berry, the trial's chief investigator and professor of nutritional sciences at King's College London, emphasized the need for long-term data to identify the specific factors driving this trend. "Over just a few generations our lifestyles, diets and environments have changed dramatically," Berry stated. "But we don't know which of these changes are increasing people's risk of bowel cancer or which ones could help reduce it. We urgently need large-scale, long-term data to uncover the true causes of early-onset bowel cancer."

In the UK, approximately 44,100 new cases of bowel cancer are diagnosed annually, with the highest incidence typically found in those aged 85 to 89. However, the rate of increase in younger demographics is a significant concern. Cancer Research UK reports that around 2,700 cases per year occur in people aged 25 to 49. Incidence rates in this age group have climbed by 62.3% since the early 1990s, rising from about 8 cases per 100,000 people in 1993/95 to 13 per 100,000 in 2018/21.

Dr. Rosiere-d-Brownson Smith, a research associate at King's College London, highlighted the necessity of a large participant pool due to the relatively uncommon nature of early-onset bowel cancer. "Although rates of early-onset bowel cancer are rising, it remains relatively uncommon, which means we need large groups of people to take part in research to help us understand why we are seeing this worrying trend," she explained. She also pointed to the increasing complexity of the modern food environment, noting that about 60% of calorie intake in the UK comes from highly processed foods, which vary significantly in their composition and processing methods.

The Prospect-UK study will collect detailed, brand-level information on actual food consumption, aiming to better understand the link between specific foods, dietary patterns, and the development of early-onset bowel cancer. This detailed dietary data, combined with long-term health information, is expected to provide crucial insights into the intricate relationship between diet and disease risk.

The initiative draws inspiration from campaigners like Dame Deborah James, known as 'Bowel Babe,' who was diagnosed with bowel cancer at age 35 and significantly raised awareness about the disease in younger populations before her passing in 2022. Dr. David Scott, director of global research initiative Cancer Grand Challenges, which is funding the study, underscored the international scope of the research. "Bowel cancer is still much more common in older people, but rising rates in younger adults pose a question we are working to answer," Scott said. "Diet and lifestyle may be part of the picture, but we need to understand what else could be contributing and how these factors interact."