With high profile media stories recently on diet and cancer, it’s timely to introduce you to guest expert and medical advisor to The Scoop on Nutrition, Dr Jane Read. In this first post we look at the role nutrition plays in eating to beat cancer. Nutrition researchers certainly know that diet plays a very important role in the prevention of cancer, however we are still a long way from curing cancer with specific foods and nutrients. There is however some growing evidence that some foods may be beneficial during cancer treatment. Unfortunately, due to scanty nutritional research, doctors often leave their patients with unanswered questions about diet during treatment. And many cancer patients feel a loss of control and look for support in alternative medicine. So this week we asked Jane for her expert advice:
About our expert:
Dr Jane Read
Dr Jane Read is a medical doctor and accredited nutritionist with a passion for nutrition and the significant role it plays in maintaining optimal health. She is currently completing her medical internship at Prince of Wales Hospital in Sydney. Jane is also an expert in cancer nutrition, having completed her PhD in this area and being heavily involved in establishing nutrition research trials within the Sydney Cancer Centre. Jane has been a member of the Complementary Therapies Committee with the NSW Cancer Institute, which is working towards better informing people with cancer about complementary therapies. She has several publications in internationally peer reviewed journals, books, and popular media and has presented her research at conferences in Australia, Europe and the USA.
What should people with cancer eat whilst having treatment?
A recent article in The Age newspaper, Melbourne had a man claiming he cured his cancer by eating 30 apricot kernels a day along with a strict vegan diet. I have lost count of the number of times I’ve been asked by clients who have cancer, about stories like this and whether it would too help beat their disease. My best advice is to take great care when reading anecdotal stories like this, as restrictive diets can lead to weight loss and nutritional deficiencies which can affect the immune system and the course of therapy. That doesn’t mean you cannot explore certain alternative therapies and nutrition approaches, just make sure they do not compromise your health or therapy and discuss your intentions with your medical team. The most important thing to remember is that the primary goal is to achieve a balanced diet, with all the challenges placed on appetite and food intake with the recommended medical treatment. To help combat problems with nausea, loss of appetite, mouth ulcers, weight loss and more, see a Registered or Accredited Practising Dietitian that specialises in oncology. Healthy eating that ensures intake of essential nutrients and adequate kilojoules for weight maintenance, will give patients with cancer the best chance of beating their disease. No single food has been shown to prevent or treat cancer however scientists believe that predominantly plant-based foods that contain important vitamins, minerals and phytochemicals interact in complex ways that give them their anti-cancer properties. Here’s a summary of some of the strongest research and likely cancer-fighting contenders:
Phytochemicals and other antioxidants such as Vitamins A, C, E and selenium, protect our cells from damage which can lead to cancer. Good sources of antioxidants include fruit such as kiwifruit, oranges, all types of berries, tomatoes, capsicum and vegetables. Phytochemicals are particularly good anti-oxidants and have been shown to slow the progression and reduce the growth of some cancers. Rich sources of these compounds include fruits particularly grapes and grape skin, vegetables (particularly cruciferous vegetables like cabbage, broccoli, brussel sprouts, cauliflower and bok choy and dark green leafy vegetables), wholegrain cereals, legumes like chickpeas and lentils, garlic and tea ( both green tea and black tea). Lycopenes are a phytochemical found in tomato based products and may help to protect against cancer, particularly prostate cancer. Although it’s not conclusive, lycopenes have also been shown to reduce the rate of progression of prostate cancer. Selenium, found in cereals, meat, chicken, fish and eggs, is also a much talked about anti-oxidant in the world of cancer. Unfortunately the evidence for selenium supplements being protective against cancer is inconsistent. It’s best not to take supplements and eat selenium-rich food instead.
Phyto-oestrogens are a group of phytochemicals that are found in plant foods including soy products such as soy beans, soy milk, tofu and tempeh. In hormone related cancers such as breast and prostate cancer, these compounds have been shown to have both cancer fighting properties as well as cancer promoting properties. It also appears from the research that eating soy or drinking soy milk early in life may help protect against cancer later in life. Soy products consumed later in life appear not to have the same benefits. Although it is good to have soy products in the diet, women with existing breast cancer or those who have had breast cancer in the past should be cautious about eating large amounts of these foods. Speak to your health professional team especially if you are taking ongoing medication, such as Tamoxifen.
Omega-3 fats are anti-inflammatory and have been shown to help protect against cancer and heart disease. The richest source of omega-3 fats in our diet is fish, particularly oily fish such as tuna, salmon, swordfish, sardines and mackerel. Flaxseeds (also known as linseeds) and chia seeds are among the richest plant source of omega-3 fats. The Cancer Council Australia recommend we have at least 2 fish meals per week. Omega-3 fats have been investigated in small trials involving cancer patients receiving chemotherapy treatment. There is some evidence to suggest that omega-3 fats when combined with a high protein and energy diet may help stabilise patients’ weight and perhaps reduce the side-effects from chemotherapy. More research is needed to confirm these findings.
Editor’s note:
Thanks Jane and welcome. It is great to have your medical expertise on board. I’m sure our readers were interested in the recent breast cancer and multivitamin study news. A position from the Cancer Council was released this week on this study in the American Journal of Clinical Nutrition. And while experts caution that there is no need for alarm, it certainly seems that the evidence is stacking up for the power of whole foods with complex nutrient synergies. So over to you readers. If you have a question for Jane to consider in a next post or have some insights to share, we’d love to hear from you.
Useful websites:
www.msk.org (go to Integrative medicine)
References:
- Haseen F et al: Is there a benefit from lycopene supplementation in men with prostate cancer? A systematic review. Prostate Cancer Prostatic Dis. 2009;12(4):325-32.
- Read J et al: Nutrition intervention using an eicosapentaenoic acid (EPA)-containing supplement in patients with advanced colorectal cancer. Effects on nutritional and inflammatory status: a phase II trial. Supportive care in Cancer. Volume 15, Number 3 / March, 2007
- Fearson KC et al: Effect of a protein and energy dense N-3 fatty acid enriched oral supplement on loss of weight and lean tissue in cancer cachexia: a randomised double blind trial. Gut. 2003 Oct;52(10):1479-86.
