A new study may shed light on why colon cancer is rising in younger adults — and it points to what many of us are eating.Researchers analyzed data from nearly 30,000 female nurses who had at least two lower endoscopies – or colon screenings before the age of 50 and filled out multiple dietary surveys over more than two decades.Their key finding: women who ate the most ultra-processed foods had a 45% higher risk of developing adenomas, which are colon polyps that can be precursors to early-onset colon cancer.Ultra-processed foods include ready-to-eat products high in sugar, salt, saturated fat, and additives.On average, participants ate 5.7 servings a day, about 35% of their total calories. Those eating 10 servings a day had the highest risk.The link held even after accounting for factors like BMI, type 2 diabetes, and fiber intake.The researchers found no association between ultra-processed foods and serrated lesions, a slower growing and less common precursor to colon cancer.The authors say ultra-processed foods don’t fully explain the growing trend but reducing them could be one step toward lowering risk.Source: JAMA OncologyAuthor Affiliations: Mass General Brigham.Sign up for our weekly HealthDay newsletter