Boston, Massachusetts — Recent research indicates that women under 50 who consume large amounts of ultra-processed foods (UPFs) may face an increased risk of developing bowel abnormalities that can lead to cancer. These foods, typically characterized by their industrial processing and lack of whole food components, are commonly high in sugars, fats, salts, and additives, which raises concerns about their health impacts.

Ultra-processed foods have sparked debate among health professionals, with some questioning the blanket classification of these items as unhealthy. Nonetheless, numerous studies link UPFs to a range of health issues, including increased susceptibility to heart disease and premature death. The latest findings suggest that high UPF consumption may contribute to the early onset of conventional adenomas, a type of bowel polyp that can precede cancer.

Dr. Andrew Chan, the study’s lead author and a researcher at Massachusetts General Hospital, emphasized the urgency of this inquiry amid rising bowel cancer rates among younger populations. “Most of these polyps do not lead directly to bowel cancer,” Chan noted. “However, it is important to understand that the majority of bowel cancers in younger individuals stem from these precursor lesions.”

The research was published in Jama Oncology and analyzed data from the Nurses’ Health Study II, which has tracked the health and dietary patterns of female nurses since 1989. From 1991, participants reported their dietary habits through food questionnaires conducted every four years, providing a comprehensive view of their diet over time.

In total, the study involved 29,105 women who completed the questionnaires and underwent colonoscopies, with none having prior histories of polyps or inflammatory bowel diseases. After following this cohort until June 2015, the researchers identified 1,189 cases of early-onset conventional adenomas and an additional 1,598 cases of serrated lesions.

Separating participants into five groups based on their UPF intake, findings revealed that those consuming the highest amounts—averaging nearly 10 servings a day—had a 45% increased risk of early-onset adenomas compared to those with the lowest intake, who averaged just over three servings daily. Notably, the study found no corresponding rise in the risk for serrated lesions.

While acknowledging the study’s limitations—such as reliance on self-reported dietary data and the inability to definitively establish causation—Chan pointed out potential mechanisms explaining the findings. He noted that UPFs are frequently associated with metabolic disorders that can elevate the risk of bowel cancer, and they may also induce chronic inflammation or disrupt gut microbiota.

Chan believes that while more investigation is needed, the evidence may similarly apply to men, further underlining the importance of understanding dietary impacts. He clarified that the study does not imply that consuming UPFs guarantees the development of cancer. “This is just one piece of the puzzle regarding rising cancer rates,” he said.

Fiona Osgun, head of health information at Cancer Research UK, highlighted the significance of the research findings in understanding the early changes in bowel health that can lead to cancer. “While this study doesn’t directly link UPF consumption to cancer risk, it sheds light on dietary influences on bowel health,” she stated. Osgun also stressed the need for policy changes to improve access to healthier dietary options, reinforcing that overall diet is more critical for cancer risk than any single food type.