Eat Your Veggies: Diet Plays a Role in Cancer Occurrence and Outcomes

Lifestyle factors – like diet and exercise habits – can interact with an individual’s genomics to influence cancer outcomes as well as disease and recurrence risk. While there is no diet or workout plan that can cure or prevent cancer, research has shown that a change in eating habits could improve outcomes, according to Doris Piccinin, a clinical dietitian specialist at the University of Pennsylvania’s Abramson Cancer Center.

Piccinin recently discussed diet and nutrition for individuals with a genetic risk for cancer at the 12th Annual Joining Forces Against Hereditary Cancer Conference.

DNA copies itself to make RNA – a process called transcription. However, when something goes wrong in this step, faulty proteins and genetic mutations can be created, thus increasing a person’s risk for cancer. Lifestyle habits like smoking can increase the chance of this happening, but recent research showed that certain nutrients can lower the risk.

Brassica Vegetables and Cancer Risk

“Early epidemiological studies pointed to the benefits of many fruits and vegetables in lowering cancer risk at that stage,” Piccinin said. “It was identified that brassica-containing vegetables (that were) rich in sulfur were able to repair DNA.”

Brassica is a family of vegetables that includes broccoli, Brussels sprouts, cabbage, cauliflower, collard greens, kale and turnips.

That same study, which was published in the International Journal of Epidemiology in 2017, also showed that for people who already had cancer, there was a 14% reduction in mortality risk with the consumption of these vegetables. Another study found that in patients with lung cancer who continued to smoke throughout treatment, there was a statistically significant decreased risk of disease progression and death in patients who had one cup cooked or two cups uncooked of brassica vegetables.

Ditch American Habits for a Mediterranean Diet

Piccinin also discussed that the standard American diet – aptly referred to as SAD – may also contribute to risk.

“The standard American diet, void of color, (full of) white pastas, rice, grains, cereals, the only vegetable a French fry, and considering ketchup as their vegetable, as well as many fried foods that are high in saturated and trans-fat, is the perfect medium for this pro-inflammatory cytokine inflammatory environment that cancer cells just love to grow in,” she said.

However, Piccinin explained that research from the American Institute for Cancer Research and the World Cancer Research Fund found that the Mediterranean diet could be beneficial.

“If we can modulate (the American diet) by a diet rich in fruits and vegetables and whole grains that provide antioxidants potentially to limit inflammation, we can slow this (cancer) growth,” she said. “In addition, foods rich in Omega-3 fatty acids like fatty fish, flax and walnuts can also lower this inflammation.”

Food Recommendations Vary by Cancer Type

Patients should work with a dietitian to determine which food plan is best for them, especially since there may be different emphases for different cancer types.

For example, Piccinin explained that patients with gastrointestinal cancers – or who are genetically prone to them – should consume no more than 18 ounces of red meat per week, and no more than two servings of processed meat, such as pepperoni, bacon and lunch meats, per month.

When it comes to hormone-driven cancers, Piccinin said that there is more of an emphasis on fat reduction.

Diet Not a Substitute for Cancer-Fighting Drugs

Finally, while a healthy diet and lifestyle changes may lead to improved outcomes, it is essential that patients do not substitute healthy eating and exercise for actual cancer treatment, as prescribed by their health care team.

“Although lifestyle factors can play a role, they should never be a substitute for traditional cancer treatment, as per your oncology team,” Piccinin said.

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