Cancer Treatment Centers of America

Plant-based diets

Author: Bridget McCrea

In case there was any doubt, your mother was right: All those fruits and veggies are definitely good for you!

The Adventist Health Study-21 supports the idea that plant-based diets rich in fruits, vegetables, legumes, grains and nuts and seeds can help cancer patients and survivors lead healthier lifestyles. The study, conducted by researchers at Loma Linda University, examined the health and the habits of Seventh-day Adventists (35 percent of whom are vegetarian versus 4 percent for the population as a whole) and studied the impact of various diet patterns from 2002 to 2014. From the 12-year-long study, researchers determined that individuals who eat plant-based diets live longer, have fewer instances of cancer, weigh less and have less heart disease. Researchers point to plant protein, omega-3 fatty acids, alpha-linolenic acid and micronutrients such as beta-carotene and vitamin C as several of the most beneficial aspects of a plant-based diet.2

Stephanie Paver, RD, CSO, CNSC, Lead Oncology Dietitian at Cancer Treatment Centers of America® (CTCA) in Goodyear, Arizona, says she has seen more patients take an interest in plant-based diets over the past few years. She says the nutritional approach is centered on “foods that are as close to whole form as possible and that come from the ground.” Following this type of eating pattern can help patients get the five to nine servings of fruits and vegetables per day recommended by the American Institute for Cancer Research.

Paver says consuming a plant-based diet is a proactive approach that one can choose to decrease disease risk and optimize longevity. The “Western diet,” common in the United States and many developed countries, is high in animal-based foods and has been correlated with heart disease, cancer, diabetes and other chronic diseases, Paver says, “we know that vegetarians and vegans tend to have much lower risks of these types of diseases, such as was shown in the Adventist Health Study-2.”

Kicking the habit

The benefits of a plant-based diet may be clear, but cutting back on high-fat, animal- protein foods and highly processed sugar-laden convenience items is not always easy. “Convenience is a big part of our culture, and many times it trumps healthy eating,” says Paver, who helps patients make behavior changes to modify their eating patterns and choose nutrient-dense foods—a change that can provide benefit during and after cancer treatment.

Acknowledging that all patients are in different stages of treatment and have different nutritional priorities, Paver aims to educate patients about the potential benefits of making healthy changes. “We certainly don’t tell anyone that they have to become vegan in order to feel better or for their bodies to heal properly,” she says, “but we do emphasize the benefits of adding more plant foods to meals while decreasing the amount of animal[-based] and processed foods in the diet.”

The reasoning behind that advice is simple, says Paver: Plants contain various phytochemicals that may enhance immune function, inhibit cancer cell growth and prevent carcinogens (cancer-causing agents) from forming, among other actions. These compounds also have antioxidant properties that can help maintain cellular health and reduce damage caused by environmental pollutants and contaminants. In addition, Paver says, preliminary evidence from animal and cell culture studies suggests that phytochemicals may play a role in cancer prevention.3

Paver says plant-based diets can also help cancer patients during and after treatment by boosting levels of vitamins C and E, which have antioxidant effects, and minerals, such as magnesium and potassium, which can become deficient in patients undergoing cancer treatment. Food provides the optimal source for these nutrients, she adds: “Try to obtain these nutrients from your diet and avoid taking them in supplement form, if possible. Consuming a balanced, plant-based diet increases your shot at getting enough of these nutrients.”

Finally, Paver says, patients who eat healthy, balanced diets that are rich in plant-based options “tend to have a better tolerance to cancer treatment.” Their quality of life is enhanced as a result, she adds, and maintaining normalcy is easier during what can be a challenging time.

Adjusting approaches to food

Wendy Greer, RN, a nurse navigator at CTCA® in Goodyear, began her own plant-based dietary journey about a year ago upon learning that her cholesterol had hit 240. By consuming only plant-based foods, she was able to whittle her cholesterol down to 165 and lose about 15 pounds in the process.

To achieve those goals, Greer began filling half her plate with fruits and vegetables, one-quarter of it with grains and the remaining 25 percent with proteinbased foods. These days her favorite foods include large salads, meatless chili, almond milk and hummus. “Everyone has different tastes,” says Greer, “but I’ve been able to adapt my eating to the point where I truly enjoy my food and never feel hungry—all while controlling my cholesterol and losing weight.”

To cancer patients who want to experience the benefits of a plant-based diet, Paver cautions against an all-or-nothing approach, as it can come with nutritional deficiencies if you are not fully informed. “Talk to your dietitian about the best options for your specific situation,” she says, “and understand that a diet that’s overly restrictive may also eliminate valuable nutrients: Fats, carbohydrates and proteins are all necessary for normal cellular function, so be sure your diet doesn’t overly restrict any one of these important nutrients.”


1. Orlich, M. J., Singh, P. N., Sabaté, J., et al. (2013). Vegetarian dietary patterns and mortality in Adventist Health Study 2. JAMA Internal Medicine, 173(13), 1230– 1238. doi: 10.1001/jamainternmed.2013.6473.

2. Palmer, S. (2014, January 22). A plant-based diet has impressive benefts, including longer life. Chicago Tribune. Retrieved February 27, 2014, from http://www.chicagotribune. com/health/sns-201401210000--tms--premhnstr-- k-k20140122-20140122,0,3834968.story.

3. Phytochemicals, Antioxidants, and Omega-3 Fatty Acids resources page. Stanford Medicine Cancer Institute. Retrieved February 27, 2014, from http://cancer.stanford. edu/information/nutritionAndCancer/reduceRisk/ phyto.htm.

4. What Is a GMO? National Cooperative Grocers Association. Retrieved February 27, 2014, from http://strongertogether. coop/fresh-from-the-source/what-is-a-gmo.