Overview
- Women with the highest intake—about 10 daily servings—had 45% greater odds of early-age conventional colorectal adenomas by age 50 versus those consuming about three servings.
- The signal appeared for conventional adenomas but not for serrated lesions, indicating possible differences in pathways to colorectal cancer.
- The analysis draws on Nurses’ Health Study II data with food-frequency questionnaires from 1991 and endoscopy outcomes through 2015, covering more than 29,100 participants over a median 13 years.
- The association persisted after adjusting for body mass index, type 2 diabetes, and fiber intake, though the study remains observational with recall limits, evolving UPF classifications, and uncertain polyp progression.
- Researchers and experts advise limiting ultraprocessed foods and keeping up with colorectal screening from age 45, while exploring hypotheses involving microbiome changes, gut barrier effects from additives, inflammation, and obesity.