Overwhelming indications from research point to the reasons for increased colon cancer in young adults.

Look around your kitchen cabinets and refrigerator, and see how many of the things you have purchased for yourself and your family may be on the list of highly processed foods. Are you finding many of them? Do you read the labels, and are you looking for healthier alternatives?

Has anybody pointed out the disturbing new indications from research regarding the incidence, some would say skyrocketing, of colon cancer in young adults? It’s time for everyone to increase their awareness, because maintaining a healthier lifestyle through food means avoiding serious health consequences.

This sleeping giant can’t be ignored. Most young adults are never told to have regular colonoscopies because they are not at risk. This is foolishness. In fact, they may be at significant risk.

Something alarming is happening to young people around the world. Colon cancer, once thought of as a disease that mainly affected older adults, is now showing up more and more in people under 50. The numbers tell a troubling story, and researchers are working hard to understand what’s happening and how to prevent it.

A Global Problem Getting Worse

Recent research shows that colon cancer rates are rising in young adults in 27 out of 50 countries worldwide. In the United States, one out of every five colon cancer cases now occurs in someone under 55 years old, compared to just one in ten back in 1995. The increases are steepest in New Zealand, Chile, and Puerto Rico, but England, Australia, and the United States are also seeing fast-rising numbers.

What makes this even more concerning is that while older adults are seeing their colon cancer rates stay steady or even drop, younger people are moving in the opposite direction. Are enough people and healthcare professionals noting these results? We have to question it since it’s usually not standard procedure to order this type of testing for younger adults. The reason for this is two-fold: standard medical procedures and insurance reimbursement. Should insurance reimbursement stop healthcare professionals from checking for a rampant increase in this cancer? We would think not.

What the Harvard Study Found

A major study published in the medical journal JAMA Oncology provides an important clue about what might be driving this trend. This is a clue, not definitive 100% evidence. Remember that.

Researchers from Harvard Medical School and Mass General Brigham followed nearly 30,000 female nurses for 24 years, tracking what they ate and checking their colon health with regular colonoscopies before age 50. The sample size and the number of years in this study should increase its importance to all of us. Most studies are not this far-ranging with this many subjects.

What they discovered was striking. Women who ate the most ultra-processed foods — about 10 servings per day — had a 45% higher risk of developing adenomas than those who ate the least — about three servings per day. Adenomas are growths in the colon that can turn into cancer over time. Dr. Andrew Chan, who led the study, explained that about 75% of colon cancers start as adenomas.

The connection held up even when researchers examined other risk factors, such as body weight, diabetes, and how much fiber people ate. “Even after accounting for all these other risk factors, the association with ultra-processed foods still held up,” Dr. Chan said.

What Are Ultra-Processed Foods?

Ultra-processed foods are the products that fill most grocery store shelves today. They’re industrial creations with five or more ingredients, often including things like artificial colors, sweeteners, emulsifiers, and preservatives. Think frozen dinners, packaged snacks, sugary cereals, candy, soda, instant noodles, and fast food. These foods are designed to be convenient, tasty, and have a long shelf life. We have provided a link at the beginning of this article.

The average American gets about 60% of their daily calories from these products. The study participants ate slightly less — about 35% of their calories came from ultra-processed foods. But even at that level, the health effects were significant. What is causing this to happen?

How These Foods Might Cause Harm

Scientists believe ultra-processed foods may damage the body in several ways. Inside your gut lives a community of trillions of bacteria that help with digestion and protect your health. Recent research shows that ultra-processed foods disrupt this delicate ecosystem.

These foods reduce the diversity of gut bacteria and lower levels of beneficial bacteria that produce short-chain fatty acids, which protect against inflammation. At the same time, they increase harmful bacteria that promote inflammation. The emulsifiers, artificial sweeteners, and other additives in these foods can damage the gut barrier, allowing bacteria to leak into the bloodstream and trigger body-wide inflammation. This association with inflammation carries on into mental health disorders, and we have seen it with nano-plastics, too.

This chronic inflammation is a known driver of cancer development. Ultra-processed foods also tend to be high in sugar, unhealthy fats, and salt while being low in fiber and essential nutrients. All of these factors together create a perfect storm for disease.

The Bigger Picture

It’s important to note that diet doesn’t explain everything. “Diet isn’t a complete explanation for why we’re seeing this trend — we see many individuals in our clinic with early-onset colon cancer who eat very healthy diets,” Dr. Chan acknowledged. Researchers are investigating other factors, such as changes in physical activity, antibiotic use, environmental exposures, and genetic factors. Of course, there are other factors, and we can’t point to only one as the sole reason for this troubling increase in this type of cancer.

However, the timing is hard to ignore. The rise in ultra-processed food consumption has happened alongside the increase in early-onset colon cancer. These foods became widespread in Western diets starting in the 1980s and 1990s, and now we’re seeing the health consequences in people who grew up eating them.

What You Can Do

The good news, as we have noted, is that diet is something you can control. Here’s what experts recommend:

1. Start cooking at home more often using whole foods like fresh vegetables, fruits, whole grains, beans, and unprocessed meats. When you buy packaged foods, check the ingredient list. If it has more than five ingredients or includes words you don’t recognize, it’s probably ultra-processed. It’s not a sure thing, but at least it’s one way to begin examining the food you put into your body and whether it might be unhealthy.

2. Cut back on sugary drinks, packaged snacks, instant meals, and fast food. Replace them with minimally processed alternatives. For example, choose steel-cut oatmeal instead of sugary cereal, fresh fruit instead of fruit snacks, and homemade meals instead of frozen dinners.

3. Increase your fiber intake through vegetables, fruits, whole grains, and legumes. Fiber helps protect your colon and feeds the beneficial bacteria in your gut.

Know the Warning Signs

If you’re under 50, don’t ignore symptoms that could signal colon problems. The most common warning signs in young people include blood in the stool, abdominal pain, changes in bowel habits, unexplained weight loss, and anemia. If you experience any of these, see your doctor right away. Many young adults report that their symptoms were initially dismissed, leading to delays in diagnosis.

The American Cancer Society now recommends that people at average risk begin colon cancer screening at age 45, down from the previous recommendation of age 50. If you have a family history of colon cancer or other risk factors, you may need to start screening even earlier.

Where do we go from here?

While researchers continue investigating the causes of early-onset colon cancer, the message is clear: what we eat matters. By choosing whole foods over ultra-processed products, we can protect our gut health and potentially reduce our cancer risk. The decisions you make at the grocery store today could shape your health for decades to come.