Seriously underestimated danger: Up to 11.5 percent of cancers found to have the same cause

A new study has revealed that obesity could be responsible for up to 11.5 percent of all cancer cases worldwide, significantly revising previous estimates that placed this figure between 2 and 8 percent. The research, led by a team at the German Cancer Research Center (DKFZ), challenges long-held assumptions about the relationship between body weight and cancer risk, suggesting that the danger posed by excess weight has been underestimated. The study analyzed data from over 458,543 participants in the UK Biobank, one of the largest repositories of health data globally. Participants were monitored for an average of 12 years, during which time more than 50,000 new cancer cases were identified. Researchers focused not only on traditional measures such as body mass index (BMI) but also on waist circumference and the ratio of waist to hip measurements. This approach allowed them to distinguish between different types of fat, particularly visceral fat, which accumulates around the abdomen, and its potential role in promoting chronic inflammation and metabolic dysfunction. Previous studies had relied primarily on BMI as an indicator of overweight or obesity, but this method fails to differentiate between muscle and fat tissue or account for how fat is distributed throughout the body. Visceral fat, in particular, functions differently from subcutaneous fat. It acts like an endocrine organ, releasing signaling molecules known as adipokines into the bloodstream. These molecules can influence cellular processes, including cell growth, division, and programmed cell death, all of which are linked to tumor development. Michael Leitzmann, an epidemiologist at the University of Regensburg, noted that the findings challenge earlier conclusions. He explained that the new methodology helped eliminate potential biases, such as the possibility that cancer itself might lead to weight loss before diagnosis. By excluding cases diagnosed within the first few years of participation, researchers ensured that the observed associations between obesity and cancer were based on long-term trends rather than temporary changes in weight. The study found that the link between obesity and cancer was particularly pronounced among women. While the overall proportion of overweight individuals who develop cancer was higher in men, the relative risk for women with excess weight was greater. However, Leitzmann cautioned against overinterpreting these results, emphasizing the need for further research to confirm whether the findings hold true across different populations and settings. The implications of the study extend beyond individual health considerations. Obesity is now recognized as a contributing factor to nearly 13 types of cancer, including breast, endometrial, and ovarian cancers. With rising global rates of obesity, the burden of cancer attributable to excess weight could continue to grow unless public health strategies address both prevention and early detection more effectively.