Dr. Mehraneh Dorna Jafari, chief of colorectal surgery at NewYork-Presbyterian Brooklyn Methodist Hospital, explains why cancer is becoming more common in adults under 50 and what researchers are learning about what could be driving this. She discusses the role of diet, the microbiome, ultra-processed foods, microplastics, and other factors in cancer risk, while also highlighting the promising advances transforming cancer care today. From AI-powered diagnostics and targeted therapies to the importance of screening and prevention, Dr. Jafari shares practical guidance and hopeful insights about the future of oncology.
Cancer has long been associated with aging, but in recent years, doctors have seen an alarming rise in colorectal cancer and other cancers among younger adults. In this episode of Health Matters, host Courtney Allison speaks with Dr. Dorna Jafari, chief of colorectal surgery at NewYork-Presbyterian Brooklyn Methodist Hospital, about what may be contributing to this growing public health concern.
Dr. Jafari explains that colorectal cancer is now the leading cause of cancer death in people under age 50 and discusses the "birth cohort effect" researchers have identified among people born after 1960. She explores several factors that may be influencing cancer risk, including changes in diet, increased consumption of ultra-processed foods, disruptions to the gut microbiome, antibiotic exposure, and the growing presence of microplastics in the environment.
The conversation also focuses on prevention. Dr. Jafari shares practical steps people can take to support a healthy microbiome and reduce cancer risk, including increasing fiber intake, staying physically active, limiting sugary beverages, and making realistic lifestyle changes over time.
Finally, she discusses the exciting advances changing the future of oncology. From targeted cancer therapies and immunotherapy to AI-assisted diagnosis and improved screening tools, Dr. Jafari explains why cancer outcomes continue to improve and why early detection remains one of the most powerful tools available—especially when it comes to colorectal cancer screening.
Chapters
00:00 – Why Are More Young People Getting Cancer?
Understanding the rise of early-onset cancers and why colorectal cancer rates are increasing in adults under 50
03:15 – Diet, Microbiome, and Environmental Risks
How ultra-processed foods, sugary drinks, antibiotics, and microplastics may influence cancer risk
07:20 – New Advances in Cancer Treatment
The shift toward targeted therapies, immunotherapy, AI, and personalized cancer care
10:15 – Screening, Prevention, and Living Healthier
Why colonoscopies remain the gold standard and the lifestyle habits that can help lower risk
Key Topics Covered
Key Takeaway
While cancer is increasingly affecting younger adults, there are meaningful steps people can take to reduce their risk. Prioritizing screening, maintaining a healthy diet rich in fiber, limiting ultra-processed foods and sugary drinks, staying active, and paying attention to symptoms can make a difference. At the same time, advances in targeted therapies, immunotherapy, and AI-driven diagnostics are helping improve outcomes and offering new hope for the future of cancer care.
Doctor Bio
Dr. Mehraneh Dorna Jafari is chief of colorectal surgery at NewYork-Presbyterian Brooklyn Methodist Hospital and associate professor of surgery at Weill Cornell Medicine. She is the director of clinical research in the department of surgery at NewYork-Presbyterian/Weill Cornell Medical Center. She is board-certified in general surgery and colon and rectal surgery. Dr. Jafari specializes in the comprehensive care of colorectal cancer patients, patients with peritoneal surface disease as well as those patients with benign colorectal disease.
Dr Jafari works with a world-renowned group of multidisciplinary specialists to help promote a patient centered treatment plan for her patients, including radiation oncologists, medical oncologists, radiologists, pathologists, gastroenterologists, and interventional radiologists. Her goal is to provide precision medicine to patients that is safe and effective.
Dr. Jafari has expertise in minimal access techniques, including laparoscopic, and robotic surgery. In addition, she has special interests in sphincter preserving surgery (helping rectal cancer patients avoid a permanent ostomy), maintaining fertility in cancer patients, and improving quality of life and bowel function after rectal surgery. Dr Jafari has been at forefront of research with regards to improving outcomes using enhanced recovery and narcotic sparing protocols.
Dr. Jafari is among a small number of surgeons who offers surgery for metastatic colon, appendiceal and peritoneal surface disease. She utilizes cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC), which involves heated chemotherapy applied directly within the abdominal cavity following removal of cancerous tumors.
Dr. Jafari's clinical research focuses on quality of life and oncological outcomes for colorectal cancer patients. Her main area of expertise is starting chemotherapy earlier in cancer treatment to allow patients to recover their quality of life sooner.
Dr. Jafari has written extensively and published in many major journals, including the Journal of the American Medical Association (JAMA), Annals of Surgery, and the Journal of the American College of Surgeons. She has led numerable courses teaching surgeons around the country how to perform minimal invasive surgery.
Dr. Jafari is actively involved in many national surgical and oncologic societies, including the American College of Surgeons, Society of Surgical Oncologists, American Society of Colon and Rectal Surgeons and Association of Women Surgeons.
Dr. Jafari: Colorectal cancer mortality has gone up in patients less than 50 compared to those who are in the screening age. The mortality overall for everybody has gone down, but for colorectal specifically for early onset, that mortality has increased.
Courtney: Welcome to Health Matters, your dose of the latest in health and wellness from NewYork-Presbyterian. I'm Courtney Allison.
This season on Health Matters, we're covering your health from A to Z, asking our experts to break down the health topics and wellness trends we're all curious about. Today, we're at O for oncology.
Colorectal cancer is now the leading cause of cancer deaths for people under the age of 50. So today, we're talking to Dr. Dorna Jafari, chief of colorectal surgery at NewYork-Presbyterian Brooklyn Methodist Hospital, to get some answers. Why are colorectal cancer deaths on the rise in young people? And why are certain cancer rates rising across the board? Dr. Jafari also shares what gives her hope for the future of cancer treatment and what we can all do to reduce our cancer risk.
Dr. Jafari, thank you so much for joining us today.
Dr. Jafari: Thank you so much. It's a pleasure.
Courtney: So Dr. Jafari, we're here today to talk about something we're all seeing. Cancer used to be associated with aging, and now it's on the rise in young people. What's going on?
Dr. Jafari: We have seen an incidence in early onset cancers in general, and that includes breast and GI cancers. We define young or early onset cancer as anyone under the age of 50. So since 2010, around that time, we've seen an increase in the incidence of cancer. By 2030, early onset colorectal cancer was gonna be the number one cause of cancer mortality in patients under the age of 50. However, we just reached that this year.
Courtney: Are you seeing this firsthand in your practice?
Dr. Jafari: Unfortunately, yes. I think being part of a large academic medical center my entire career, at first the thought was that it was anecdotal just because you see more complicated cases, but it turns out that when you actually look at the data, it's across not only the US but globally, the numbers have increased. Overall, all cancer mortality is going down. A lot of that has to do with a lot of changes and improvement in the way we treat cancer, specifically lung and breast cancer. Unfortunately, colorectal cancer mortality has gone up in patients less than 50 compared to those who are in the screening age.
Courtney: You said colorectal is now the leading cause of cancer death under the age of 50.
Dr. Jafari: Yes.
Courtney: Do we know what's behind that?
Dr. Jafari: We don't exactly know what's behind that. Cancer is not very simple. What people have seen is they're calling it this birth cohort effect that began in the 1960s, and essentially what they saw is that in individuals who were born after 1960, there's a fourfold higher colorectal cancer risk.
Courtney: Wow.
Dr. Jafari: If you look at the 1960s, environmentally it's very different, right? Antibiotics, hormones, what we're putting in our food, plastics. Diets have changed a lot, and that may have changed the bacteria in our gut. Ultra-processed food, it's not something that our bodies were used to, right? We were eating a lot more fiber than meat as we sort of evolved as human beings until recently. So those Western diet patterns have definitely increased GI cancers and specifically colorectal cancer numbers.
Courtney: What might ultra-processed foods have to do with rising cancer rates? One JAMA study we came across looked at nurses over a long period of time and showed that more ultra-processed foods led to growth that could become cancer.
Dr. Jafari: So that study shows that those dietary patterns have really impacted early onset advanced colorectal adenomas, which is basically the precancerous lesions. High fructose is not something that was normally in our diets before the 1900s. If you have more than two servings of that, like sugar-sweetened beverages, that can basically increase your relative risk factor of early onset colorectal cancers by like twofold, which is a lot. It's something easy to eliminate, easier said than done, but I think sodas or sugary drinks, just look at the back of the label.
Courtney: I think another thing people are frightened of are microplastics.
Dr. Jafari: Right.
Courtney: Can you talk about microplastics as a potential carcinogen?
Dr. Jafari: People have talked about microplastics a lot. It's a growing body of literature. We just don't know exactly how it affects everyday cells, but the emerging evidence is there is some causations with it. There are some studies that show that there's a high concentration of it around the tumor tissue, but I think everything is very preliminary. But I think it's still important because plastic's not supposed to be in your body. Because again, it's around the 1950s, '60s that we had this plastic boom, and there is enough evidence that you should try to eliminate it. And if you can go to plastic substitutes in the house, you should try to do that. It's actually been shown that even a little amount of effort, like not using bottles, helps decrease the microplastics in your system. So little changes makes a difference.
Courtney: You also mentioned antibiotics earlier and the microbiome. Is there any evidence that overprescription of antibiotics or a microbiome lacking in diversity contributes to these cancer rates?
Dr. Jafari: There definitely is data behind that. We, as children, got a lot more antibiotics, as I think now there's a stewardship, and we try not to give antibiotics for, like, let's say, viral syndromes. I remember every time I had a cough as a child, I would get antibiotics, which was unnecessary, and that definitely changes your microbiome. But there have been studies that show that some cancers who respond well to, for example, radiation, like rectal cancer, there's certain bacteria that if you have it, have better responses to radiation.
Courtney Host: If you had to prioritize just a few habits for people to help reduce cancer risk, what would they be?
Dr. Jafari: So there's little things you can do to keep your microbiome healthy. Having thirty grams of fiber in your diet every day does keep a healthier microbiome, and that's been studied over and over again. Diet is incredibly important, and that high fiber, it's not just good for your gut health, it's also good for your cardiovascular health, so that's one thing that I would hone in the most. Getting rid of the microplastics as best as you can, and then exercise helps you with your stress levels and to be in a better cardiovascular health. You have to take it step by step because when you try to be like, "Okay, I'm really scared, I'm gonna get rid of everything that's processed foods," especially if you're working and you've got kids, it's impossible. I think you just have to start slow and be like, "Okay, I'm gonna s- now substitute all sugary drinks with water, but I'm gonna do it slowly." If you had, like, a soda every day, you go to, like, three times a week, and then you go slowly.
Courtney Host: I really appreciate your moderate, realistic approach to all this. So switching gears, I'd love to talk about the bigger picture of cancer care today and what's giving you hope. I think cancer treatment is really scary and difficult for people, and so wondering what's on the horizon that's exciting for you.
Dr. Jafari: There's a lot happening in cancer care. Before, like, the last four or five years, what we were doing a lot was there's a cancer, and we're basically gonna give it cytotoxics, which is basically chemotherapy, which kills not only the cancer cells, but also other things. And now, the entire cancer world is moving towards targeted therapy, so all the basic science research that's been funded for the last 20, 30, 40 years is really coming to a fruition, and what we're seeing is that whether it's utilizing your immune system to fight the cancer or targeting specific targets within the tumor itself, you target it, and you kill those specific cells, is kind of what's in the horizon. And so it's, it's a very exciting time.
Courtney Host: I also saw that there was some news about GLP-1 drugs, that patients taking the drugs showed lower risks of developing cancer and disease progression, better survival, and improved responses to treatments compared with people who are not taking GLP-1s. It sounds like the research is still early, but any comments on that?
Dr. Jafari: You have to take it with a grain of salt because it's not comparing it to people who are essentially not on GLP-1s, but it's important to also remember that it has to do with obesity and metabolic syndromes. There is some data that when you have a metabolic syndrome, your response to treatment is not as good. So a lot of those improvements is also that obesity-related, metabolic syndrome-related effects on cancer and cancer progression itself. So if you eliminate that, you most likely can change the outcomes.
Courtney: So, I know teams across NewYork-Presbyterian, Weill Cornell, and Columbia are all working with AI to analyze imaging in a way that will better predict breast cancer risk. Are there examples you're seeing of AI helping with cancer treatment?
Dr. Jafari: They can be additive tools to the physician, where they basically look at, like, a billion images and come up with these computational models of picking things up. Eventually, I think what'll happen with a colonoscopy is it'll be like this polyp is cancer, this polyp isn't, and then we m- potentially may not have to send it to pathology once that AI has been confirmed. I think it's gonna be very interesting because if you can diagnose things much sooner and perhaps know the mutation of the cancer, you can then target therapy and then cure that without a surgery, without cytotoxics. That's hopefully where the future's going to go.
Courtney: Screening is one of the most powerful tools we have. What should people know about colonoscopies, and we're hearing about newer blood-based screening tests, too.
Dr. Jafari: The gold standard is colonoscopy. Why? Because colonoscopy p- picks up precancerous lesions. It's not only a diagnostic, but it's a screening tool, meaning that if you have a precancerous or an adenoma, it gets cut out. The issue with the current blood test, like the ones that pick up the DNA in the stool, is that if it's negative, it doesn't mean that you don't have those precancerous lesions. It picks up the cancerous stuff. So the blood test, if you have, like, a stage I through III colorectal cancer, is about 87.5% sensitive. It's specific for advanced cancers, but if you have a precancerous lesion that may become a cancer in a couple years, you're gonna have to wait for it to be cancer for it to pick it up. And because it's not 100%, it means that if it's negative, it doesn't mean that you don't have it. That's why colonoscopy is the gold standard, because we get rid of things that could become cancer and diagnosis at the same time. That's why colorectal cancer mortalities overall compared to other diseases is better because of the screening and diagnostic tools.
Courtney: So switching gears a little, how important is a holistic approach to cancer treatment, especially in treating young people?
Dr. Jafari: A holistic approach is incredibly important. The issue is, especially with early onset, anybody who's working and taking care of their parents or has kids, is that there's a lot of other things going on. So across all cancer centers, social workers, et cetera, are very involved in our cancer care. For early onset colorectal cancer, fertility preservation's incredibly important for patients. For men, a little bit easier than women because you just can bank your sperm. For women, it's a little bit more cumbersome to harvest eggs, but there are fertility specialists that take care of cancer patients. We have nutritionists on call. If you have kids and we don't know how to tell the children that mom or dad has cancer, there's child-life services at a lot of the cancer centers.
Courtney: So we've talked about so much today when it comes to cancer. What do you hope people take away from this conversation?
Dr. Jafari: If you have symptoms, you should be seeking medical care. However, mortality rates for cancer are improving or are going to improve. Screening, like colonoscopies, mammograms, that's gonna decrease the number of people who have cancer. So just stay up to date with all of that. Try to eliminate the things that are easy for your lifestyle, and that does make a difference. That's my biggest thing to patients is, like, you wanna have a glass of wine? Have a glass of wine. You wanna have a piece of cake because it's your birthday? That's not gonna make the cancer grow. We can just do what we can do.
Courtney: Dr. Jafari, thank you so much for joining us today and breaking down this really complex topic.
Dr. Jafari: Absolutely. Happy to help.
Courtney: Our many thanks to Dr. Dorna Jafari. I'm Courtney Allison.
Health Matters is a production of NewYork-Presbyterian. The views shared on this podcast solely reflect the expertise and experience of our guests.
To learn more about Dr. Jafari's work with patients, check out the show notes.
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