A recent significant study has highlighted that eleven types of cancer are showing an upward trend in individuals aged 20 to 49. These cancers include bowel, breast, ovarian, liver, kidney, gallbladder, pancreatic, thyroid, multiple myeloma, endometrial, and oral cancer. Researchers have indicated that except for oral cancer, all these types are associated with obesity, potentially due to heightened levels of insulin and inflammation.
Professor Montse Garcia-Closas, of the Institute of Cancer Research in London, emphasized the urgency for further investigation and prompt action. She stressed the necessity of addressing obesity at all ages, particularly in children and young adults, through enhanced public health strategies and increased access to effective interventions to curb the escalating cancer rates.
The study conducted by experts at the ICR and Imperial College London revealed that while the incidence of several cancers has surged in younger adults over the past two decades, traditional risk factors like smoking, alcohol consumption, red or processed meat intake, low fiber consumption, and sedentary lifestyle have remained stable or declined before diagnosis. This indicates that these factors are unlikely to completely account for the spike in cancer cases, unlike the consistent rise in overweight and obesity levels since 1995, which could be pivotal in the increased cancer diagnoses.
Despite the rise in body mass index (BMI), the study published in BMJ Oncology concluded that BMI alone does not wholly explain the overall uptrend in cancer among younger adults in England. The researchers believe that there must be additional underlying causes contributing to this rise, whether identified or still unknown.
While nine out of the eleven cancers exhibit increasing rates in both younger and older adults, bowel and ovarian cancer are specifically rising among younger age groups. Notably, for bowel cancer in younger women, rates linked to BMI showed a faster increase compared to those not associated with BMI. This suggests that other factors are likely playing a role in the escalation of these cancer cases.
Various suspected contributors such as ultraprocessed foods, antibiotic usage, and air pollution have been suggested, but their trends in the UK have not shown consistent increases, highlighting the need for a comprehensive investigation into all potential factors driving the rise in cancer rates.
In 2023, approximately 31,000 cancer cases were diagnosed in individuals aged 20 to 49 in England, representing around one in every 1,000 people. In contrast, 244,000 cases were reported in individuals aged 50 to 79, roughly one in every 100.
Professor Garcia-Closas mentioned that a substantial portion of bowel cancer cases in younger individuals could be attributed to being overweight or obese, with a significant percentage linked to combined known risk factors such as obesity, lack of physical activity, alcohol consumption, and smoking.
The research team emphasized the importance of conducting extensive long-term studies to identify all biological and environmental factors contributing to the surge in cancer rates among young adults. However, they highlighted obesity as a crucial public health concern, underscoring the need to address and reduce obesity rates, especially in children and young people. The study utilized national cancer registry data for England spanning from 2001 to 2019.
