Colorectal cancer is the second leading cause of cancer-related deaths in the United States, and its incidence is rising—particularly among younger adults. While genetics and lifestyle factors such as physical inactivity and smoking play a role, mounting evidence points to a powerful modifiable factor: diet.
As a cardiologist, you might wonder why colorectal cancer—a disease of the digestive tract—belongs in the cardiovascular conversation. The answer lies in the profound overlap between heart-healthy and cancer-preventive diets. By promoting dietary patterns that reduce cardiovascular risk, we also support cancer prevention and overall health.
In this post, we’ll explore the relationship between diet and colorectal cancer, highlight foods that increase or reduce risk, and offer practical strategies for patients to protect both their digestive and cardiovascular systems.
A recent article from Health Matters by NewYork-Presbyterian Hospital breaks down how certain foods influence colorectal cancer risk, based on expert input from Dr. Felice Schnoll-Sussman, a gastroenterologist at Weill Cornell Medicine. She emphasizes that while diet isn't the only factor, it’s one of the most important and modifiable ones.
The colon and rectum are directly exposed to the foods we eat—and the breakdown products of digestion. Over time, a poor diet can damage the lining of the colon, alter gut bacteria, and create an inflammatory environment that contributes to the development of polyps, which can become cancerous.
1. Processed Meats and Red Meat
According to the World Health Organization (WHO), processed meats such as bacon, hot dogs, sausage, and deli meats are classified as Group 1 carcinogens—meaning there is convincing evidence they cause cancer, particularly colorectal cancer. Red meat (beef, lamb, pork) is classified as a probable carcinogen (Group 2A).
Why the risk? These meats contain heme iron and compounds like nitrites and nitrates, which can convert into carcinogens in the body. High-temperature cooking (like grilling) further produces harmful substances such as heterocyclic amines and polycyclic aromatic hydrocarbons.
2. Low-Fiber Diets
Diets lacking in fiber from whole fruits, vegetables, legumes, and whole grains are associated with an increased risk of colorectal cancer. Fiber plays a crucial role in digestive health by adding bulk to stool, promoting regularity, and feeding beneficial gut bacteria.
3. High Sugar and Ultra-Processed Foods
Sugary beverages and ultra-processed foods are associated with increased inflammation and insulin resistance—two mechanisms implicated in both cancer and heart disease. A study published in The BMJ found that high intake of ultra-processed food was linked to a greater risk of colorectal cancer in men.
1. High-Fiber Foods
Dietary fiber, especially from whole plant sources, helps regulate digestion and supports a healthy gut microbiome. A large meta-analysis published in Lancet found that higher fiber intake significantly reduced colorectal cancer risk.
Foods high in fiber include:
Whole grains (oats, brown rice, quinoa)
Legumes (lentils, beans, chickpeas)
Fruits and vegetables
Nuts and seeds
2. Fruits and Vegetables
These are rich in antioxidants, vitamins, and phytochemicals that help reduce inflammation and oxidative stress. Cruciferous vegetables like broccoli, kale, and Brussels sprouts contain sulforaphane, a compound studied for its cancer-preventive properties.
3. Omega-3 Fats and Healthy Oils
Fatty fish like salmon and flaxseed oil contain anti-inflammatory omega-3 fatty acids. Replacing saturated fats (found in red meats and butter) with heart-healthy oils like olive oil may also offer protective effects.
4. Fermented and Probiotic-Rich Foods
A growing body of research supports the role of the gut microbiome in cancer development. Probiotic-rich foods like yogurt, kefir, sauerkraut, and kimchi can help maintain gut microbial balance, which may contribute to reduced cancer risk.
There is striking overlap between dietary strategies for cardiovascular disease prevention and colorectal cancer reduction. For example:
A Mediterranean diet—rich in whole grains, vegetables, healthy fats, and lean proteins—is linked to lower risks of both colorectal cancer and heart disease.
Reducing saturated fats and processed foods is beneficial for both arterial and colon health.
Weight management, a key factor in cardiovascular risk, also reduces colorectal cancer risk.
In fact, obesity, especially central obesity, is an established risk factor for colorectal cancer and atherosclerosis alike.
While diet is crucial, colorectal cancer prevention also includes timely screening. Colonoscopies can detect precancerous polyps and allow for their removal before they turn into cancer. The American Cancer Society now recommends starting screening at age 45, earlier for those with a family history or other risk factors.
Cardiologists play an essential role in reinforcing this message. Patients at high cardiovascular risk often share overlapping dietary and lifestyle challenges—and may not be seeing a primary care provider regularly. Encouraging your patients to follow up on colon cancer screenings can be a life-saving referral.
Fill half your plate with vegetables and fruits, aiming for color and variety.
Choose whole grains over refined ones—think brown rice instead of white, or whole wheat pasta.
Limit red meat to a few times a month, and avoid processed meats as much as possible.
Incorporate legumes and plant-based proteins like lentils, tofu, and beans.
Snack on nuts and seeds, and use olive oil in cooking instead of butter or lard.
Stay hydrated and limit sugary drinks.
✅ Include fermented foods regularly to support your gut microbiome.
Diet is a powerful tool in the prevention of colorectal cancer, just as it is in the fight against heart disease. The two go hand in hand—when you protect your heart with healthy food choices, you’re often protecting your gut, too.
As cardiologists, we have a unique opportunity to help patients not only manage their cardiac risk but also take meaningful steps toward comprehensive, long-term health. By promoting fiber-rich, plant-based diets and reducing intake of processed foods and red meats, we can help prevent one of the deadliest yet most preventable cancers.
The message is clear: your plate can be your prescription—for heart health, digestive health, and beyond.
NewYork-Presbyterian Health Matters (2025). The Relationship Between Diet and Colorectal Cancer.
https://healthmatters.nyp.org/the-relationship-between-diet-and-colorectal-cancer/
World Health Organization. Carcinogenicity of consumption of red and processed meat.
https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf
The BMJ (2022). Ultra-processed foods and colorectal cancer risk.
https://www.bmj.com/content/378/bmj-2022-071543
American Cancer Society (2023). Colorectal Cancer Prevention and Early Detection.
https://www.cancer.org/cancer/colon-rectal-cancer/detection-diagnosis-staging/screening-tests-used.html
