In a recent discussion on my talk show, a listener asked the featured cancer haematologist: “When my daughter was diagnosed with leukaemia, I was given absolutely no advice on nutrition. I did a lot of research on the internet, got information through word of mouth, but nothing from the doctors. When nutrition plays such an imperative role in fighting cancer, why does it remain so ignored?”
This is the question most cancer patients and their families would love to know the answer to. Yes, there is a lot of conflicting information out there, but it is important to be able to find the authentic and useful. Just a simple search on open source databases like PubMed (which I did, post the show) throws up more than 30,000 studies linking nutrition to cancer.
It is important to note that in their hectic schedule of saving lives, doctors may not have the time to look into the nutrition of individual patients. This is left to the nutritionist on call, caregivers and families, network connections, associated support groups and forums.
Eating well can be a challenge when you have cancer. Some people find that their eating habits change only slightly, while others find that eating well is really hard. Many people are somewhere in-between. How your eating is affected will depend on the type of cancer and the treatment you receive.
Says Meera, a non-Hodgkin’s lymphoma patient: “You do have to experiment a bit. What worked for your cancer buddy may not work for you. So experiment with your food and be aware that it may not be easy for a while.”
Here are some tried and tested recommendations.
- Eat apples, basil and cranberries. They contain ursolic acid that acts synergistically with your anti-cancer therapy.
- Increase consumption of cruciferous vegetables. They are rich in sulphur, which has anti-cancer compounds.
- Include papaya and pomegranate in your diet.
- Add turmeric and pepper to your list of spices.
- Try to use whole grains for wheat, rice and pasta (they smoothen spikes in blood glucose.)
- Savour cooked and stewed tomatoes.
▲ Excessively toasted breads and baked goods (they contain acrylamide, a potent carcinogen).
▲ Highly processed food, MSG and artificial colouring.
▲ Artificial sweeteners such as aspartame.
From the doctors' desk
Among the many discussions I have had, the most relevant ones were with Donald Abrams, chief of haematology and oncology, San Francisco General Hospital and Colin Campbell, of The China Study fame.
While Dr Campbell advocates a low-protein diet, Dr Abrams makes quite a few interesting observations. He says most people cannot properly digest milk and cheese as most of us are lactose intolerant; we just don’t know it. However, butter and yoghurt are okay. Though dairy is the most potent source of calcium, he advises patients to get their calcium from green leafy vegetables and tofu. And, to ensure optimum calcium absorption, vitamin D supplementation is important, he says.
Whole soya food is highly recommended. This should include soyabeans, soyamilk and tofu.
Patients are cautioned not to take highly concentrated antioxidant supplements. Whenever the two oxygen molecules separate, they become free radicals, called reactive oxygen species, which knock into our DNA, leading to ageing or cancer. Antioxidants take those free radicals out of circulation so they don’t do any damage. Now, it turns out that radiation therapy and some chemotherapy drugs work by creating free radicals of oxygen to do damage to the cancer cell’s DNA. There is a concern that taking antioxidant supplements may actually diminish the effectiveness of the radiation and chemotherapy.
Abrams agrees with the controversial school of thought linking sugar consumption to malignant tumour growth. Eating food high in sugar leads to steep blood-sugar spikes. He said that this stresses your body and causes it to secrete large amounts of insulin and insulin-like growth factor, both of which promote inflammation and cause cancer cells to divide.
He also recommends regular consumption of mushrooms, specifically recommends medicinal mushrooms like shiitake, reishi, cordyceps, maitake, turkey tail and oyster mushrooms.
Eating to starve cancer
Using nutrition to defeat cancer is not a new idea. Dr William Li, head of Angiogenesis Foundation, a nonprofit group that is re-conceptualising global disease fighting, talks about the concept of anti-angiogeneis, or preventing growth of blood vessels that feed a tumour.
Angiogenesis is the formation of new blood vessels and this is critical for the growth and spread of cancer. Blood supply is necessary for all tumours to grow beyond a few millimeters. So, the body’s ability to balance angiogenesis prevents blood vessels from feeding cancers. Many food items contain natural cancer-starving molecules that prevent tumours from acquiring blood vessels. These include fruits, herbs and spices. Cheese is another potent weapon. Hard cheeses like Gouda and Edam contain vitamin K2, which kills cancer cells directly.
Overall, cancer rates are lower in India than in the west. Studies point to factors like our level of spice consumption (spices are the most antioxidant packed class of food), relatively low intake of meat, consumption of pulses, high intake of fresh fruits and vegetables and mostly a plant-based diet.
So, what difference do such dietary changes make? We don’t know. But, each of the above recommendations is based on research results from the cancer community. The suggestion is that following these recommendations, even to make incremental changes, might have some advantages in our effort to live well with cancer.
**Priya V. Menon is scientific media editor at TrialX/Applied Informatics Inc. She manages and hosts CureTalks, an international online radio talk show on cancer research and health care.**