Diet and obesity have been implicated in the outcomes of patients who have been diagnosed with various forms of cancer. What one chooses to eat can have profound effects on his/her health, particularly when it comes to reducing the risk of cancer. Because cancer is a cumulative disease from chronic damage to healthy cells and tissue, diet and nutrients play a vital role in enhancing the host response. Diet is the foundation of integrative medicine, and unlike age or genetics, dietary choices can be changed by the patient with the goal of reducing cancer risk. With every bite we take, we are either feeding disease or fighting it.
Working with a professional who specializes in nutrition (e.g. clinical nutritionist) can have an important bearing on what your journey after cancer looks like. Because of this, the American Cancer Society recommends survivors be given nutritional assessments as soon after the diagnosis as possible, yet this rarely happens. A meta-analysis of 117 studies that followed 209,597 cancer survivors found those who consumed high quality diets and followed healthy eating habits had a significantly lower mortality rate. Additionally, there was an association of higher mortality rates if survivors consumed a Western diet, which is highly inflammatory.
Due to the overwhelming amount of information (and sometimes inaccurate information) on the internet, it is also important to discuss nutrition with your healthcare team because there are differing degrees of evidence to support different diet modifications for various types of cancers. For example, a study found patients diagnosed with colorectal cancer had a lower mortality rate if they increased their fiber intake after being diagnosed, but there are no randomized trials so far to further support the implementation of fiber intake guidelines.
Current nutrition guidelines provided in June 2020 by the American Cancer Society are as follows:
- Follow a healthy eating pattern at all ages.
- A healthy eating pattern includes:
- Foods that are high in nutrients in amounts that help achieve and maintain a healthy body weight and fuel your cells;
- A variety of vegetables-dark green, red, and orange, fiber-rich legumes (beans and peas), and others;
- Fruits, especially whole fruits with a variety of colors; and
- Whole grains.
- A healthy eating pattern limits or does not include:
- Red (unless organic and grass-fed) and processed meats;
- Sugar-sweetened beverages; or
- Highly processed foods and refined grain products.
- It is best not to drink alcohol at all.
- People who do choose to drink alcohol should limit their consumption to no more than 1 drink per day for women.
- A healthy eating pattern includes:
The American Cancer Society recommendations are a good place to start, but if you aren’t meet your goals, you may need a tailored approach based on your nutritional needs.
Dietician? Nutritionist? Clinical Nutritionist? Who should you see? The difference in these titles lies in the amount of training and the qualification to provide medical nutrition therapy to individuals. Technically, anyone who wants to give nutritional advice can call themselves a nutritionist. A board-certified clinical nutritionist keeps current on the latest advances in nutrition science and translates them into nutritional interventions that can treat and prevent chronic diseases like cancer. Individualizing diet therapy to meet the individual needs of a given person is critical to long-term adoption of healthy eating. The repetitive and sufficient exposure to cancer-fighting compounds can reduce cancer risk.
- Schwedhelm C, Boeing H, Hoffmann G, Aleksandrova K, Schwingshackl L. Effect of diet on mortality and cancer recurrence among cancer survivors: a systematic review and meta-analysis of cohort studies. Nutrition reviews. 2016 Dec 1;74(12):737-48.
- Rock CL, Doyle C, Demark‐Wahnefried W, Meyerhardt J, Courneya KS, Schwartz AL, Bandera EV, Hamilton KK, Grant B, McCullough M, Byers T. Nutrition and physical activity guidelines for cancer survivors. CA: a cancer journal for clinicians. 2012 Jul;62(4):242-74.
- Rock CL, Thomson C, Gansler T, Gapstur SM, McCullough ML, Patel AV, Andrews KS, Bandera EV, Spees CK, Robien K, Hartman S. American Cancer Society Guideline for Diet and Physical Activity for cancer prevention. CA: A Cancer Journal for Clinicians. 2020 Jun 9.