It is no longer a question of whether nutrition should be a fundamental piece of the global treatment in cancer care, but rather how. Under the care of the right physician – one who is current with information, experienced and qualified – anyone dealing with cancer can learn how to implement effective dietary and nutritional strategies to improve their current state of health, enhance treatment outcomes, prevent recurrence and mitigate disease-related impact on quality of life.
NUTRITION IN CANCER CARE IS A SCIENCE
Despite the robust evidence for the role of nutrition in cancer care,1-3 when patients are engaged in a purely conventional cancer treatment approach, most often their individual nutritional needs are either overlooked or dismissed entirely. There can be many reasons for this, but most often it simply has to do with the assigned oncologist. There is tremendous variability among oncologists – just as there is among naturopathic physicians, medical physicians and other types of health care practitioners. No two are going to be exactly alike in their knowledge base and approach to care, and each is entitled to their ‘opinion’ that can be easily misconstrued as ‘medical fact’. Many people undergoing cancer care are advised by their oncologist that ‘nutrition doesn’t matter’ or ‘don’t change how you’re eating’ or ‘do not take any nutritional supplements because they will interact with your treatments’. Such advice is counter to the evidence and is misleading to patients, often due to the oncologist’s limited knowledge and understanding about nutrition in cancer as well as their own unsubstantiated and blanket viewpoint that all antioxidants will negatively interact with medications and radiotherapy.
“There are in fact two things, science and opinion; the former begets knowledge, the latter ignorance.”
In medicine, if we view health and disease through a narrow lens, ultimately it impacts patient outcomes. Advice to avoid nutritional strategies in cancer care is contrary to evidence informing us that, independent of the type of treatment strategy, the quality of pre-treatment nutrition is one of the only methods that sustains significant impact on patient outcomes 3 months or longer post-treatment.4,5
Many oncologists vary in their position on naturopathic and nutritional care in cancer. Some advise patients to engage in intravenous vitamin C therapy, while others don’t even want patients to change the way they eat because they fear the nutrients in healthy food may interact with their chemotherapy or radiation. Recently, there is a greater trend toward oncologists modernizing their viewpoint on nutrition in cancer care and embracing an integrative approach with other health care practitioners, such as naturopathic doctors – but this still represents only a small portion of oncologists in Canada.
It’s important to recognize that while there are definite considerations for food or nutrient interactions with drug, radiotherapy or surgical interventions, there is also a vast amount of science and research that guides naturopathic doctors specializing in cancer care in the dietary, nutritional and adjunctive therapies we recommend to patients.
THE SENSIBILITY OF INTEGRATIVE CANCER CARE
Let’s use an analogy in nature to illustrate the dynamic between disease, cancer treatments and nutrition. Would you expect to revive a withered plant embedded in unhealthy soil? The soil is the terrain that provides nourishment for the plant – the healthier the soil, the stronger the plant and the better it responds to water and sunlight. If the soil were stripped and was suddenly the harsh elements of external forces (stormy weather, extremes of temperature or drought), how would you expect it to survive if it wasn’t strong and vital to begin with?
Surgery, chemotherapy and radiation are often part of the treatment regimens most will endure as part of their cancer care. These are forces that demand great physical and emotional strength to overcome. While cancer is obviously far more complex than the plant-soil-environment analogy, it serves as an important reminder for us to observe and appreciate the fundamental laws of nature. If we neglect the simple pieces of the equation, it can spell a formula for disaster.
Good sense informs us that if we are strong, vital and healthy leading into battle, the less damage we will encounter, the easier the recovery and the greater the likelihood for victory against the enemy – in this case, cancer.
If chemotherapy and radiation is the ammunition we use against the enemy, nutrition is our body armor that offers protection against the opposition.
Observations in nature, clinical experience, robust outcomes data from scientific and clinical studies and a respectful approach to informed, mutual decision making between doctor-patient (one that considers a patient’s personal values), ultimately define the sensibility of the modern evidence-based medical model in integrative cancer care.6
WHAT SHOULD I EAT IF I HAVE CANCER?
There is no straightforward answer to what diet you should follow if you have cancer. There are many phases to cancer care: the pretreatment phase, treatment phase (chemo, radiation, surgery), post-treatment healing phase and maintenance (prevention of recurrence). The individual needs during each of these phases will vary depending on a multitude of factors. While there are some general guidelines you can follow, specific nutritional needs must be met and may require modification along the way depending on the type of cancer, the select therapies, tolerability of treatments and the nature of the disease.
For example, in the case of gastrointestinal tumors (such as gastric cancer or colon cancer), intestinal absorption of nutrients is compromised and is a significant factor in prognosis.7 Despite a healthy diet, nutritional deficiencies are inevitable, but can be addressed though vegetable juicing (to optimize absorption) or with intravenous or parenteral nutrition.
REPLACE PROCESSED FOODS WITH “WHOLE FOODS”
While nutritional care does need to be individualized, there are some general guidelines you can follow. Start by eating a ‘whole food’ diet.8 A whole food diet is free from processed foods, unhealthy fats, refined sugars and alcohol. Instead the diet consists of fruits, plenty of vegetables, moderate amounts of complex carbohydrates (from grains like quinoa, brown rice, millet and oats), lean proteins (from fish, poultry, lean meat, beans, soy) and healthy fats (from oils, nuts and seeds).
Whole, unprocessed foods retain more of their nutrition and are more easily digested than their processed counterparts, thereby optimizing nutrient absorption and energy from food, giving you more out of what you consume. Processed foods also create more inflammation in the body and inflammation is a driving force in the initiation, progression and recurrence of cancer.9,10
PREVENT MALNUTRITION + REDUCE INFLAMMATION = BETTER OUTCOMES IN CANCER
Up to 85% of all patients with cancer develop clinical malnutrition, which negatively affects their response to therapy, increases the incidence of treatment-related side effects and can decrease survival.11 Early intervention to prevent malnutrition has shown to promote recovery, reduce hospital stay and improve prognosis and quality of life.2 To compound the nutritional conundrum, certain cancer treatments themselves (such as chemotherapy, radiation, surgery, immunotherapy and stem cell transplant) can make it difficult to eat well due to associated side effects (mouth sores, nausea, vomiting, reduced appetite, diarrhea, constipation, pain, difficulty swallowing, fatigue, depression) and can alter the way the body uses nutrients.
Malnutrition weakens the immune system, causing a drop in white blood cells and reducing resistance to infection. As a consequence, chemotherapy treatments may be delayed or missed or in some cases even stopped altogether, compromising the treatment outcome and the patient’s chance for full recovery.
Studies have found certain biomarkers of systemic inflammation (parameters that can be measured in blood, such as C-Reactive Protein or CRP) can predict malnourishment in cancer patients and are correlated with overall prognosis.12-14 These biomarkers of inflammation are useful to monitor throughout the course of treatment as functional indicators of disease status and provide therapeutic targets for nutritional intervention.15. Studies on high-dose intravenous vitamin C (HD-IVC) and the impact on inflammation in cancer reveal that HD-IVC significantly reduces CRP and pro-inflammatory cytokines, offering therapeutic value in cancer care alone and in conjunction with certain chemotherapies and radiation.16-20
NUTRITION IS A LIFELONG COMMITMENT TO YOUR HEALTH
Nutrition clearly plays a critical role in the management of cancer throughout the spectrum of care – from the pivotal time of initial diagnosis and pre-treatment preparation, through to the long-term continuum of care when the goals are to prevent recurrence, reduce risk of death from disease related to treatment (such as heart disease and stroke), increase longevity and improve quality of life. With professional guidance, nutrition can be powerfully leveraged to engage the body’s innate ability to heal and adapt to adversity.
The right elements of food and nutrition provide strength to the vital force within all of us to help fight even the most destructive of diseases – like cancer – and regain the inner balance that aligns our mind, body and spiritual health.
“Let food be thy medicine and medicine be thy food”
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