Ashlee Williams, MD (Host): Colon cancer, something you don't need to worry about if you're under the age 50, right? Not quite. In recent years, there's been a concerning rise in cases of colon cancer among younger adults. But why is this happening? What role do diet, lifestyle, and genetics play in this trend? And most importantly, what can you do to lower your risk?

 Welcome to the Healthier You podcast. I'm Dr. Ashlee Williams. And today, I'm joined by Dr. Alex Jow, a board-certified gastroenterologist at Kaiser Permanente. Together, we'll explore the factors behind this rise in colon cancer and discuss practical steps that you can take to reduce your risk and potentially improve your chances for early life-saving detection. Dr. Jow, thanks so much for being here.

Alexander Jow, MD: Dr. Williams, thanks for having me join you on this really important topic.

Host: Yes, it's such an important topic. There's been such a rise in these cases, especially in people under 50. So, it is concerning that there's been a rise in colon cancer cases. How common is colon cancer?

Alexander Jow, MD: So, colon cancer is going to affect about 150,000 people this year in 2025. We know for men this is the third most common cancer that men will experience, and then for women this is the fourth most common cancer. But more concerning is actually for people under the age of 50, this is going to be the number one cancer killer for both men and women.

Host: So, can we talk about what is causing this rise in our cases?

Alexander Jow, MD: Just to go back to kind of the cases, I mean, we've known over the last 10 years, we're seeing a steady about 2 2% increase in people under the age of 50 starting to get these early-onset colon cancers under the age of 50. And, you know, that's the million-dollar question, what's really causing this?

And, unfortunately, we don't really know, but there are some research really linking certain things that do show as risk factors for younger people. And the number one thing that I've seen and that the research has shown is that diet, really, there is a connection between what we're eating and our risk for colon polyps and colon cancer. Some of these things include lower fiber diets can be associated with colon cancer. We do know that fruits and vegetables and things that are high in fiber are good for the microbiome and can be protective for the colon. And recently, the WHO did name red meat and processed meats as per possible carcinogens. And certainly, the research has showed that high intake of processed meats or red meats can increase the risk of colorectal cancer.

And finally, with this obesity epidemic where we see a lot of high ultra-processed foods, refined sugars in our diet, we do know that high sugar diets, obesity can also be a risk factor for colorectal cancer.

Host: Okay. Yes. Ultra-processed foods. And just a quick plug. We do have a great podcast on ultra-processed foods. Can you talk a little bit about what signs and symptoms people should look for?

Alexander Jow, MD: Yeah, certainly. So, with early-onset colon cancer or early colon cancers in general, there are no symptoms. And this is why screening is so important because a lot of times these cancers will have no symptoms. However, sometimes with more advanced colon cancers, we can see some symptoms and you certainly, if you notice these symptoms, talk to your doctor about whether you need further testing. These can include rectal bleeding with or without pain, blood in your stool, or in the toilet during your bowel movements or after your bowel movements. It's a change in your bowel pattern, so a movement towards, say, more diarrhea or constipation, where typically you had more regular bowel movements. On blood work, sometimes anemia, specifically iron-deficiency anemia, can certainly be a sign of a colon cancer.

And then, there's other kind of symptoms that there's a crossover for other different GI disorders that we often mistake for something like irritable bowel syndrome, but certainly could be a sign of something more serious. This could include bloating, cramping, abdominal pain, a change in the stool caliber, so maybe pencil-thin stools instead of kind of those thicker stools, change in your bowel habits in terms of your ability to have a bowel movement, so new straining or feeling like it's difficult to have a complete bowel movement. And then, sometimes things like weight loss or fatigue or just loss of energy can be a sign of colon cancer as well.

Host: Yeah, I think that's an important tip to pay attention to your body, right? You know, as doctors, we have all this medical information that we can help use to help diagnose things, but you've been living with your body all this time. So if you notice changes in your stool caliber or you're noticing weight loss or fatigue, it's really important to schedule an appointment with your primary care doctor to discuss those symptoms. Can you talk a little bit about when people should be screened for colon cancer?

Alexander Jow, MD: Up until probably 2021, the colon cancer screening age was recommended to start at the age of 50. And really, researchers started to notice that there was this increased incidence of younger people getting colon cancer. There were certainly some high profile in the media of, if you remember, Black Panther, the actor Chadwick Boseman died very quietly, but he had a struggle with stage IV colon cancer and died at the age of 43.

And so, the American Cancer Society actually in 2018 started to make a recommendation that we should really be screening people at a younger age. Recommended the age of 45. And then, the USPSTF, which is the US Preventative Services Task Force , which really make guidelines for the vast majority of primary care doctors, changed their guidelines, decreased the age from 50 to 45 in 2021.

And so for really the last four years, we really have been increasing our efforts to start screening and bring awareness that the screening age has decreased and to really start those conversations with your primary care doctor about your screening modalities, how you want to do it, and talking with your families and friends about screening.

Host: Yeah. And just a quick question about the different ways that we can get colon cancer screening because I do have patients that come in, like they've just turned 45, and they're not quite ready to go through a colonoscopy, because they feel like it's too invasive. Can you just talk a little bit about other screening options, especially for low-risk adults?

Alexander Jow, MD: Yeah, absolutely. So, I mean, we're in this really exciting era where there's so many new modalities that we have options for, and so you can kind of tailor the type of screening to the patient and kind of the factors that are important to them. And I always tell my patients, the best screening test you're going to get is the screening test that you're actually going to get. So, there isn't like a perfect one.

Certainly, the two-tier one tests available for us that are both available at our institution at Kaiser Permanente. There is FIT testing, which is a stool test. This is a fecal immunochemical test. The pros of this test, it's an at-home test. You get a kit mailed to your home. You just have to produce a stool. And this test checks for microscopic evidence of blood in your stool. And so, the thought process is that tumors or colon cancers or even advanced polyps have very fragile blood vessels. So when the stool passes by the cancer, we get a little bit of oozing of this microscopic blood that we can detect in our stool test. So, these tests are very easy. You don't have to do sedation. You don't have to do a preparation. You don't have to take a day off of work. And you just send it out, do it once a year. And we know the detection rates, the one-time detection rates are about 80% for FIT testing, which is pretty good for screening tests.

And then, obviously, there is the gold standard test, which is colonoscopy, which is something that I do day in and day out, what I love to do. It is a great screening tool, but certainly is a more invasive procedure. It does require a little bit more of a preparation process. It does have some slight increased risks, but certainly has the benefit of being a very good screening test, but also a preventative test.

Host: I love the enthusiasm for colonoscopies. Do you have any tips for reducing the risk of developing polyps or colon cancer?

Alexander Jow, MD: Yeah. So, I think it goes back to what are the known links and risk factors for colon cancer and certainly what are the modifiable risks, right? So, unfortunately, sometimes cancer happens and there's nothing we can do about it, but there are some modifiable risk factors. So for my patients who are young, who are saying, "What can I do?" and actually, even if you're older, "What can I do to prevent colon cancer, colon polyps?" And I always say, "You are what you eat," right? So, diet is the number one thing we have control of every day, what we put into our bodies.

So, I say, really, you should be trying to have a balanced diet. I say eat the rainbow. If you eat things that are greens and that have, browns and oranges and reds, you're really getting an array of nutrition, fiber that's good for your diet. So, you really, again, should be really trying to put in a lot of whole grains, a lot of non-processed foods. As I said, probably leaning more towards lean proteins like chicken or fish, rather than high amounts of red meat or processed meats, but diet is a really big thing.

And then, certainly, lifestyle changes, like staying active. We do know that a sedentary lifestyle can be a risk factor for colon cancer. And actually, regular activity like 150 minutes a week, which it just comes out to be 30 minutes a day for five days of the week, can really protect you from your risk of developing colon cancer.

And then finally, things like smoking and alcohol. I mean, tobacco has always been a known link for many, many colon cancer. But in terms of alcohol use, you know, the Surgeon General just came out with his recommendations that there is really no amount of alcohol that is healthy for you anymore. And we do know that there's a lot of links with alcohol use, or increased alcohol use in colon cancer. So, certainly making sure that you moderately do any of these things. And certainly, if you smoke, quit. And if you don't smoke, don't start smoking.

Host: Great tip. And I also love that you are what you eat, never gets old. I've been hearing that since I was a child. I'm telling my kids. So, that's really great information.

So, we learned a lot about colon cancer and what we can do to prevent it. Here are the top takeaways. One, colon cancer is common, and more than 20% of new cases are in young adults who range in age from their mid-20s to their late 50s. Two, sedentary lifestyle, obesity, smoking, heavy alcohol use, low fiber, high fat diets, and diets high in processed meats and high fructose syrup may be contributing to the recent rise in cases among young adults. Three, it's important to be familiar with your body and be aware of symptoms, which can include rectal bleeding, changes in bowel patterns, a change in the size or shape of your stool, and unintentional weight loss or fatigue. Four, routine screening starting at the age of 45 is the best way to prevent colon cancer. Talk to your doctor about your personal risk factors and which method is right for you.

For more information from our experts, visit kp.org/doctor and listen to more episodes of Healthier You wherever you get your podcasts. If you enjoyed this episode, be sure to share it with others who may find it helpful. Thank you. And from all of us at Kaiser Permanente, be well.