Most people know that cancer is a complex disease, and there are a lot of different things that increase your risk, including genetics, age, smoking, exposure to chemicals, and certain lifestyle choices. Most people don’t think about their diet as potentially increasing their cancer risk. Although no single food can determine whether you’ll develop cancer, research shows that what you eat can significantly affect your overall health and long-term cancer risk.

The good news is that nutrition is a lifestyle factor that can be controlled. By understanding the connection between your diet and overall health, you can make more informed decisions. Even small, sustainable changes to your eating habits can positively impact your body, including reducing the risk of certain cancers.

What Is the Typical American Diet?

The term “American diet,” often called the Standard American Diet (SAD), generally refers to common eating patterns seen across the United States. While everyone’s individual diet varies, Americans tend to eat:

• Highly ultra-processed foods
• Large portion sizes
• Excess added sugars
• Refined carbohydrates
• Processed and red meats
• Excessive sodium
• Only a few fruits, vegetables, whole grains, and legumes

Overall, many Americans fall short of recommendations for nutrient-dense foods such as fruits, vegetables, whole grains, and fiber-rich plant foods. At the same time, a significant portion of daily calorie intake comes from highly processed convenience foods.

How Does Your Diet Influence Cancer Risk?

Scientists are still learning about the complex relationship between nutrition and cancer. While diet does not directly cause most cancers, certain eating patterns may contribute to conditions that are associated with increased cancer risk.

Weight Gain and Obesity

One of the strongest links between diet and cancer involves body weight.

Diets high in calories, added sugars, and processed foods can contribute to weight gain and obesity. Excess body weight has been associated with an increased risk of several cancers, including:

• Breast cancer after menopause
• Colorectal cancer
• Endometrial cancer
• Kidney cancer
• Esophageal cancer
• Ovarian cancer
• Pancreatic cancer

Although there are still questions about the link between excess weight and cancer, research suggests that obesity increases cancer risk due to hormonal changes and inflammation that can promote cancer growth. Maintaining a healthy weight through balanced nutrition and regular physical activity can be an effective strategy for reducing your cancer risk.

Chronic Inflammation

Inflammation is the body’s natural response to injury or illness. While short-term inflammation helps healing, ongoing inflammation can cause cellular damage over time.

Some dietary patterns, particularly those high in processed foods and low in fruits and vegetables, may promote chronic inflammation. When inflammation persists, it can create an environment that may support cancer growth.

Insulin and Hormone Changes

Eating highly processed foods that are high in added sugars and refined carbohydrates can lead to insulin resistance, a condition where the body’s cells become less responsive to insulin. Eventually, insulin resistance may result in elevated insulin levels and other metabolic changes.

Additionally, obesity can alter hormone levels, including estrogen and other growth hormones, which may play a role in the development of hormone-sensitive cancers. It’s important to note that while sugar doesn’t directly cause cancer, poor dietary habits that lead to obesity and metabolic issues can increase risk over time.

Foods and Dietary Patterns Associated With Increased Cancer Risk

Rather than labeling individual foods as “good” or “bad,” researchers generally focus on overall eating habits. However, some foods have been more consistently linked to increased cancer risk than others.

Processed Meats

Processed meats are meats preserved through salting, curing, smoking, or chemical preservatives. Examples include:

• Bacon
• Sausage
• Hot dogs
• Deli meats

According to the World Health Organization, regular consumption of processed meat is associated with an increased risk of colorectal cancer. Because of this, it is recommended to avoid processed meats or limit how often they are eaten.

Excessive Red Meat Consumption

Red meats, such as beef, pork, and lamb, can be part of a healthy diet, but experts generally recommend moderation. As with processed meats, diets that contain large amounts of red meat have been associated with a higher risk of colorectal cancer. Research also indicates links with prostate and pancreatic cancer. To create a more balanced dietary pattern, consider replacing some red meat with poultry, fish, beans, and lentils.

Ultra-Processed Foods

Ultra-processed foods (UPFs) often contain multiple additives and undergo more processing than other foods. Examples include:

• Packaged snack foods
• Sugary cereals
• Fast food
• Soft drinks

Emerging research suggests that diets high in ultra-processed foods may be associated with obesity, cardiovascular disease, and some cancers.

Sugary Foods and Beverages

As mentioned earlier, sugar itself does not directly cause cancer. However, diets high in sugary foods and beverages can contribute to weight gain, obesity, and metabolic changes that are associated with an increased cancer risk. Rather than eliminating sugar, focus on limiting added sugars and aim to create an overall balanced eating pattern.

Foods That May Help Support Cancer Prevention

While it would be wonderful if specific foods guaranteed cancer prevention, that’s not the case. But certain dietary patterns are known to promote better health and lower the risk of chronic disease.

Fruits and Vegetables

A diet high in fruits and vegetables provides fiber, antioxidants, vitamins, and minerals. Eating a variety of colorful produce ensures a wide range of beneficial nutrients.

Whole Grains

Whole grains retain more of their natural fiber and nutrients compared to refined grains, which are significantly modified. Healthy whole-grain options include:

• Oats (rolled or steel cut)
• Wild and brown rice
• Whole wheat products
• Buckwheat
• Ancient grains, such as quinoa, amaranth, einkorn, millet, and spelt

Diets rich in fiber have been associated with lower cancer risk and better overall digestive health.

Plant-Based Proteins

Plant proteins offer fiber and important nutrients while often containing less saturated fat than animal-based products. Adding foods like beans, lentils, and chickpeas to your diet can help support long-term disease prevention and overall health.

Healthy Fats

Healthy fats, such as unsaturated fats found in nuts, seeds, avocados, and fish, are important for overall health and may reduce cancer risk. Other examples of healthy fats include avocados and olive oil.

Lean Protein Sources

When considering cancer risk, lean proteins are generally considered safer than red meat. Examples of lean protein options include fish, poultry, and plant proteins.

Practical Ways to Improve Your Diet

Healthy eating does not require perfection. In fact, small changes that you can stick with are often the best.

Consider these simple strategies:

• Fill half your plate with fruits and vegetables
• Limit processed meats
• Replace sugary drinks with water
• Cook more meals at home
• Read nutrition labels
• Choose whole grains over refined grains as often as possible
• Focus on gradual improvements more than drastic changes

Small Changes, Big Health Benefits

Remember, no single food directly causes or prevents cancer. But a diet high in processed foods, red and processed meats, and added sugars can raise your cancer risk. To boost overall wellness and reduce cancer risk over time, be sure to incorporate a variety of fruits, vegetables, whole grains, and healthy fats into your diet.

If your eating habits aren’t perfect, that’s alright! Every healthy choice counts. Small, consistent changes can make a meaningful difference in your health.

Cancer Guidance and Support in Colorado

Rocky Mountain Cancer Centers encourages regular cancer screening whenever possible. Early detection of cancer makes it easier to treat!

Learn more about screening for several types of cancer.