The benefits of plants in cancer

BY KAREN SPURGEON WELCH, MD, ABFM, Fellow, Integrative Medicine and Behavioral Health, Clinical Instructor, Family Medicine, The University of Texas Medical Branch at Galveston

Cancer is both a most-feared and mostcommon disease of our times, with over 1.5 million new diagnoses in the United States expected in 2015. Upwards of one in three people in the United States can expect to receive a diagnosis at some point in their lifespan, leaving few who are untouched, personally, socially, or professionally by the disease. The patient and family experience is often one of helplessness and disempowerment, compelling a search for interventions that are within reach.

Food, being a locus of control for most, is a potential space for hope. Indeed, while the topic of food choice impact on cancer is complex and difficult to study, evidence as reported by the World Cancer Research Fund, suggests that a diet high in plant foods can offer cancer protection. The American Cancer Society and the World Health Organization, along with their counterpart organizations, recommend a diet high in a variety of fruits and vegetables for the prevention of cancer.

With a lead hypothesis being that some plants contain certain cancer-protective substances, it stands to reason that some plants would be more beneficial than others. The World Cancer Research Fund (WCRF) International pooled evidence in an Expert Report demonstrating evidence supporting, for example, fruits and nonstarchy vegetables as preventive for mouth, pharynx, larynx, and esophagus, allium vegetables as preventive for stomach cancers and colorectal cancer, and foods containing lycopene and selenium for prostate.

Many of our best conventional chemotherapy drugs are plant-derived substances. Periwinkle provided us with vincristine, vinblastine, and vinorelbine. The yew tree yielded paclitaxel. Mayapple brought us podophyllin. Considering the pathophysiology of cancer, treatment is a much different animal from prevention. These are toxic substances and exactly what is needed for targeting a cancer growing within the human body.

As an Integrative and Behavioral Fellow working in an integrative oncology consultation service, we are often faced with the question of what botanicals are appropriate during and after treatment. Patients want to be empowered to do something. We focus our advice on interventions that couple well with conventional therapy and support the body through treatment and recovery. We aim to cultivate the soil so that the patient may flourish as the weeds are being removed.

We routinely recommend a diet that is high in plants with a variety of colors, weighted toward foods that are anti-inflammatory and high in natural antineoplastic chemicals. This type of diet not only helps the patient to maintain a healthy weight and strengthen the body as it’s unwelcome visitor, cancer, is being targeted with treatment but also prepares the patient for survivorship preventing future cancer as well as cardiovascular disease.

A colorful, plant-based diet can be made more robust with botanicals that have current evidence for chemoprevention, as detailed in Integrative Oncology (Weil Integrative Medicine Library), including garlic, quercetin, and curcumin. Garlic demonstrates apoptotic and immune modulating activity, has epidemiological evidence to support prevention in several types of cancers, and can be easily, safely, and deliciously added to cuisine. Garlic pairs well with onion, a great source of quercetin, which demonstrates anticancer activity and appears to reduce incidence and mortality from several cancers as part of the diet. Curcumin, a main component of curry, with a growing body of evidence demonstrating a desirable effect on carcinogenesis, can also be added beautifully, along with it’s glowing orange hue, to culinary creations.

Mushroom polysaccharides, found in turkey tail, reishi, shiitake, and maitake species, have been shown to stimulate the immune system, activating natural killer cells, T-cells, B-cells, and macrophage-dependent responses. These mushroom extracts are being researched as immune-modulators in treatment and prevention of cancer. Extracts are available in capsule form and can compliment treatment. Some of these mushrooms also make delicious additions to a meal.

Green tea, consumed throughout Asia for thousands of years, makes a lovely addition to a healing diet. This plant shows potential as a chemo-preventive and antineoplastic agent, interfering with multiple steps in carcinogenesis. Consumption of green tea can be a healthy ritual and also counters cancer-related fatigue.

Aside from direct anti-cancer effects, the plant kingdom often provides solutions for cancer and treatment-related symptoms. Ginger is useful for nausea. Senna, prunes, and psyllium are great for constipation, and pectin-containing foods are useful for diarrhea. Vibrant seasoning such as oregano, rosemary, and thyme can curb dysgeusia.

Botanicals are a hot area of research, with promising potential, and we can make use of what we know now, starting in the common kitchen. For patients who want to tap into this reservoir, we often recommend a book by Rebecca Katz and Mat Edelson The Cancer Fighting Kitchen as a resource.

Cancer is a life-changing event. It is a diagnosis that when received, or even pondered, often invokes the desire for control and can be a powerful stimulus for the adoption of behaviors that are supportive of health. This can be a good opportunity for joining with a patient or loved one to explore the mystery and healing potential of plants.

Abrams, D, Weil A. Integrative Oncology. Oxford: Oxford UP, 2014. Katz, R. The Cancer-fighting Kitchen: Nourishing Big-flavor Recipes for Cancer Treatment and Recovery. Berkeley: Celestial