Ultraprocessed Foods Tied to Rising Colon Cancer Risk in Young Adults

Colon cancer, once considered a disease mostly affecting older adults, is now showing up in growing numbers among younger people — and researchers believe our diets may be playing a major role. A new study published in JAMA Oncology has found a strong link between ultraprocessed food consumption and the risk of developing colorectal polyps, a common warning sign for colon cancer.

The study followed over 29,000 adults for 13 years, tracking their eating habits and health outcomes. Researchers found that those who consumed 10 or more servings of ultraprocessed food each day had a 45% greater risk of developing colorectal polyps. These polyps are growths in the colon or rectum that can become cancerous over time.

Ultraprocessed foods include packaged snacks, instant noodles, sugary breakfast cereals, processed meats, soft drinks, and many frozen ready-to-eat meals. These foods are often high in added sugars, unhealthy fats, and artificial ingredients, while offering little nutritional value. According to the study, a higher intake of these foods was linked with more polyps — even after accounting for other risk factors like family history, smoking, and physical activity.

The lead author of the study, Dr. Mingyang Song, an epidemiologist at Harvard T.H. Chan School of Public Health, said the findings are especially troubling because ultraprocessed foods make up a large portion of the average American diet. “Our results suggest that cutting back on ultraprocessed food could be a practical and effective way to reduce early colorectal cancer risk,” Dr. Song told The New York Times.

Colorectal cancer is the second leading cause of cancer death in the U.S., but it’s also one of the most preventable. While rates among older adults have decreased due to regular screenings, colon cancer diagnoses among adults under 50 have more than doubled since the 1990s, according to the American Cancer Society.

Health experts say the sharp rise in early-onset colon cancer is alarming and may be tied not only to diet, but also to other lifestyle changes such as reduced physical activity, disrupted gut health, and rising obesity rates. However, food choices are one of the easiest factors to change — and researchers hope studies like this one can encourage younger adults to think twice before reaching for heavily processed meals.

Doctors now recommend that people begin colon cancer screenings at age 45 instead of 50, and encourage anyone experiencing symptoms like blood in the stool, persistent stomach pain, or unexplained weight loss to see a doctor right away.

Still, the growing body of evidence suggests that prevention should start even earlier — with healthier food choices during childhood and young adulthood. Swapping ultraprocessed foods for fruits, vegetables, whole grains, and lean proteins may help lower the risk of future health problems, including colon cancer.

“Small changes in diet can have a big impact,” Dr. Song said. “We need to start thinking about how what we eat today shapes our long-term health tomorrow.”