Chiropractic + Naturopathic Doctor

Nutrition and Cancer

By Victoria Coleman   

Features Nutrition Wellness

Two in five people are now being diagnosed with cancer.

Two in five people are now being diagnosed with cancer.1 It has been shown that 40 per cent of cancers may be preventable by diet and lifestyle improvement alone, and this, coupled with the agreement between major, respected organizations – such as the American Institute for Cancer Research, the American Cancer Society, and the National Cancer Institute – suggests that cancer may largely be a preventable disease, suggests there is a role we can play in affecting the occurrence and outcome of this diagnosis.2,3

We are what we eat, drink, breath, think and eliminate. This article will discuss the role of nutrition and nutritional supplementation not only in the prevention of cancer but also in supporting the patient living with cancer. The principles behind this make perfect sense and there is evidence to support extending the recommendations for preventing cancer for use with those living with cancer.



The over-consumption of calories is a major issue in many disease states. Never before have we seen such an over-caloric, nutrient-deficient population. Food of high caloric density and low caloric nutrition has resulted in obesity and disease. It is known obesity increases one’s risk for cancer but, interestingly, it has now been shown that caloric restriction, even slightly past normal weight needs, has a protective effect on cancer. This approach is called CRON-Calorie Restriction with Optimal Nutrition. The notion is to consume fewer calories (approximately 80 per cent required to maintain normal weight) but ensure all necessary nutrient needs in vitamin, minerals and other nutrients are met. The restriction is focused on the amount of calories consumed. Science has supported this theory in extending the life span of many species and it is currently being tested on primates. Studies in mice have already shown reduction in tumour growth, prolonged survival along with spontaneous tumour regression with caloric restriction.2

Considering the correlation of obesity with cancer, it appears advantageous to give further consideration to the role that consuming slightly less than the accepted “normal” amount of calories may play.

Eating the anti-cancer diet

Eating a diet high in fruit and vegetables – particularly in their raw forms – protects against cancer (and many other diseases too). There are so many mechanisms underlying how and why eating a diet rich in fruits and veggies is effective, but a key point to acknowledge is it is not likely due to any one single nutrient but rather the protective effect of several of the nutrients. Block et al. (Nutr Cancer, 1992) reviewed hundreds of papers on cancer and fruit and vegetable intake. In summary, 128 of 156 of the studies showed a statistically significant reduction in risk in the upper quintiles of fruit and vegetable intake.4  The recommended servings range from 5.4 to 6.2 servings per day; however, ideally, it would be 10 servings per day. Eating more cruciferous vegetables such as broccoli, cauliflower, cabbage and brussels sprouts – which contain sulphorophane – is recommended. Studies have supported the intake of cruciferous vegetables in reducing risk of breast cancer, non-Hodgkin’s lymphoma, bladder and lung cancer, to mention just few.

Due to its high lignin content, incorporating flax seed powder has shown positive effects in reducing the risk of prostate cancer – the same has not been shown using flax seed oil. It is best to grind the flax seeds up in a coffee grinder regularly to keep a viable amount of lignan activity.

Watching foods’ glycemic index and load is also important. There has been an association shown between foods that are high in glycemic load and the risk of gastric, digestive tract, ovarian and colon cancer. There is also a suggested link between diabetes and an increased risk of cancer, supporting, again, the rationale to consume a diet low on the glycemic index and glycemic load of foods and maintain a healthy body weight.

What NOT to consume

Considering the foods we should avoid is also important in the anti-cancer diet. These include foods that are high in trans fat and ones that throw the Omega 6:3 ratio out of balance; refined grains that are reduced in fibre content; and red meat. Red meat and processed meats are associated with a significant increase in colorectal cancers. The production of heterocyclic amines that results from cooking meat, particularly at high temperatures, may be a key issue with meat consumption. Anyone who has read T. Colin Campbell’s book The China Study (BenBella Books, December 2004) may also be convinced that animal products in general may be smart to avoid; however, not all anti-cancer diets promote this concept. Of course, it makes sense, when eating an animal product, to chose one that is grass-fed and organic, thus reducing exposure to antibiotics, hormones and feed that is used to  produce high-weight animals.

What to supplement

It is also important to remember supplements are just that . . . they supplement an already good diet. It is prudent to consider the science on cancer prevention using supplements and implement a few strategies that one’s diet just cannot address fully, especially in high-risk people. A good foundation of essential fatty acids (EFAs), vitamin D and a multivitamin mineral are great places to start to ensure nutrient deficiencies are addressed. 

However, there are other supplements to consider:

  1. Probiotics – Probiotics have been shown to strengthen the immune system, a large part of which resides in the gut. Although many of the studies have been animal studies, there is a strong emergence of information regarding how probiotics affect human health. There is a strong theoretical basis to the suggestion that probiotics may have a role in preventing cancer, specifically colon cancer, by reducing procarinogenic enzymes including beta-glucoronidase, nitroreductase and azoreductase.2
  2. Oral enzyme therapy – We understand “we are what we eat” but we also are what we absorb. Ensuring proper absorption of nutrients is essential for full health. It was shown that not only in impaired digestion, but also in the in the healthy gut, using digestive enzymes improves carbohydrate and protein bioavailability in the small intestine. After discussion on how important our diet is to obtain key nutrients from our foods, it is best to ensure we are able to absorb those nutrients fully. Not only in the prevention of cancer, but also in the treatment of the cancer patients, enzyme therapy – specifically the proteases such as papain, typsin and chymotrypsin – have been shown to exhibit anti-tumour and anti-metastatic effects.5,6


The safe and effective use of antioxidants

Assisting the nutritional health of a patient with cancer is so important, considering that, often, in traditional oncology treatment, little attention is paid to lifestyle and diet. Many times the recommendations are in opposition to the anti-cancer diet strategies – with recommendations of eating high-fat, high-caloric, refined foods – with an attitude of “it does not matter what you eat, just eat to keep weight up.” This seems counterintuitive to what we know about the body, the immune system and the role nutrients play in health.

 There is also the fear that using supplementation – specifically antioxidants – during cancer treatment such as chemotherapy and radiation would blunt and interfere with the effectiveness of those therapies. Why this disconnect? This stemmed from the concept that these therapies work by generating free radicals to induce cellular death and that antioxidants would neutralize these free radicals. Simone II et al. (Alternative Therapies 2007) reviewed the evidence in over 50 human trials involving 8,521 patients using beta carotene, vitamins A, C, and E, selenium, cysteine, B vitamins, vitamin D3, vitamin K3 and glutathione. Use of these supplements in 5,081 people showed there was no interference in the traditional therapeutic modalities – in fact, the supplements enhanced the effects of these modalities, decreased their side-effects, protected normal tissue, and, in some, increased their survival.7

There are possibly several mechanisms of action for this, but one is quite interesting. Due to membrane disruption, cancer cells accumulate antioxidants to a high level which can shut down the cells’ oxidative reactions needed for generating energy and surviving. Healthy cells do not have this membrane defect and do not excessively accumulate antioxidants. A study in 2005 by Pathak looking at non small cell lung cancer showed that combination therapy of chemotherapy and antioxidant therapy did not reduce the effectiveness of the traditional therapy. Even more interesting, the pretreatment with antioxidants vitamin C, A, E and beta carotene significantly enhanced the growth inhibitory effects of cisplatin, and other chemotherapeutic agents.8
Supporting the cancer patient with proper calories is important but ensuring the calories are from a healthy source, with the adjunct of supplementation, should be an integral part of their therapy. Working with integrative care providers that will evaluate the patient’s individual needs and risk factors is essential.

Following the anti-cancer diet – along with an open discussion with all health-care providers on what they may implement to assist with their treatment to ensure the best results possible – makes perfect sense for these patients.

Note: for specific dosing and forms of antioxidants, patients should be encouraged to work with health-care providers to adequately meet their individual needs and the needs of their particular form of cancer.


  1. Simone II C, Simone N, Simone V, Simone C. Antioxidants and other nutrients do not interfere with chemotherapy or radiation therapy and can increase kill and increase survival, Part I. Alternative Therapies 2007, 13:22-28
  2. Donaldson M. Nutrition and cancer: A review of the evidence of an anti-cancer diet. Nutrition Journal 2004, 3:19
  3. Schachter M. Integrative Oncology for clinicians and Cancer Patients. ISOM 2010, 25(4):169-193
  4. Block G, Patterson B, Subar A: Fruit, vegetables, and cancer prevention: a review of the epidomological evidence. Nutr Cancer 1992, 18:1-29
  5. Wald M, Olejar T, Pouckova P, Zadinova M: Proteinases reduce metastatic dissemination and increase survival time in C57B16 mice with Lewis lung carcinoma. Life Sci 1998, 63:L237-243
  6. Wald M, Savadova E, Pouckova P, Zadinova M, Boubelik M: Polyenzyme preparation Wobe-Mugos inhibits growth of solid tumors and development of experimental metastases in mice. Life Sci 1998, 62:l43-48
  7. Simone II C, Simone N, Simone V, Simone C: Antioxidants and other nutrients do not interfere with chemotherapy or radiation therapy and can increase kill and increase survival, Part II. Alternative Therapies 2007, 13(2):40-47
  8. Pathak AK, et al. Chemotherapy Alone vs. Chemotherapy plus high Dose Multiple Antioxidants in Patients with Advanced Non Small Lung Cancer. Journal of the American College of Nutrition 2005 24 (1) 16-21

Dr. Victoria Coleman is a 1994 graduate of CMCC and a BSc in Kinesiology specializing in Fitness Assessment and Exercise Counseling. Working with patients over the years, it became her mission to teach people that everything you eat, breath, drink, and think affects your health. This fuelled her desire to further expand her career and continue her studies. She is an avid follower of the Institute for Functional Medicine and is currently working toward her certification in Functional Medicine. Dr. Coleman is also the president of Douglas Laboratories/Pure Encapsulations Canada.

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