Lowering Cancer Risk
For a new book, Dr. Weil and Donald I. Abrams, M.D., the former director of Clinical Programs at the University of California, San Francisco Osher Center for Integrative Medicine, assembled a team of experts to assess what the emerging field of integrative oncology has to offer cancer patients.
Published by Oxford University Press, Integrative Oncology is aimed at health professionals, but can be understood by cancer patients and their families as well as by health-conscious individuals concerned with cancer prevention and treatment options. The book is the first in a planned series on integrative medicine's role in various medical specialties including psychiatry, rheumatology, asthma and immunology, pediatrics, women's health and others. Here, in the second segment of a two-part interview, Dr. Abrams discusses how integrative medicine fits into cancer prevention. In the first part, he described his practice of integrative oncology and how integrative medicine can enhance cancer treatment.
Let's talk about prevention. What are the basic tenets of integrative medicine (IM) in cancer prevention?
IM dietary recommendations for cancer prevention are much the same as they are for individuals being treated for cancer - consume a plant-based diet focusing on an array of fruits and vegetables of different colors. Cruciferous vegetables such as broccoli, cauliflower and cabbage contain a cancer preventing compound so potent that is being investigated as a chemotherapy agent. Eat berries for their beneficial phytonutrients and antioxidants. Emphasizing fruits and vegetables, whole grains, nuts, cold water fish that provide omega-3 fatty acids (fish eaters have a reduced risk of cancer) is the best nutritional strategy.
At the same time, you should reduce your intake of animal fats in general and red meat and dairy products in particular - this could help control any cancer-promoting inflammation in the body. Stay away from refined sugar and heavily refined carbohydrates because of their effect on insulin production and insulin-like growth factors, which promote inflammation and are also associated with cancer cell division.
And don't forget physical activity. There's a chapter in the book about how important exercise is for cancer risk reduction. We know that it helps protect against colon and breast cancer, and possibly endometrial, lung and prostate cancer. Physical activity is also essential for maintaining a healthy body weight since obesity is a major risk factor for many cancers. All told, more than 180 epidemiological studies confirm a cancer-protective effect for physical activity.
Many recommendations for cancer prevention are lifestyle based. How can IM professionals get their patients to comply with these in the age of "just give me a pill"
This is a problem that speaks to the need for changes in our medical system so that patients aren't expecting that medication will solve all their problems. Right now, we do have a "find it, fix it" medical system mentality, largely because that's what is taught in medical school and that is what gets reimbursed. As a result, physicians don't spend enough time talking about prevention and teaching people to live healthy lives. Insurers don't reimburse for well-being visits.
Another issue is the fact that we're also an over-supplemented society. We see patients who come in with a bag full of supplements that they've read about on the internet or heard about - something their boss' nephew took to cure his cancer. These patients are also looking for a quick fix, but instead of pharmaceuticals, they want quick- fix supplements.
Are there specific strategies for the prevention of specific cancers, or is the preventive lifestyle essentially the same for all types of cancer?
That's a good question. If I can use an analogy: when we see a patient with established cancer - which I likened to a weed when we spoke about integrative oncology's approach to cancer treatment - our goal is to make the soil that the weed grows in as inhospitable as possible for cancer. Our approach here is pretty much the same for all types of cancer. But there are some things that may help reduce the risk of specific cancers. For example, eating soy foods during adolescence works pretty well to reduce the risk of breast and prostate cancers in Asians who maintain a traditional Asian diet (when they move to the U.S., their diet changes and their risk becomes closer to a western one than an Asian one). Reducing your intake of red meat probably goes a long way to protect against a number of different cancers, but has been documented best for colorectal and pancreatic cancers. Unfortunately, we can't do test tube studies to show how red meat affects cancer risk, and we can't even study this in animals, because if an animal has a human tumor, its immune system has been altered to accept the tumor. And we can't do a study to randomize red meat eaters and non-eaters, so we have to rely on population studies.
Just how effective are the preventive measures? Isn't the risk of cancer mostly genetically determined?
Some cancers are genetically determined, but in the developed world we know that 30 percent of avoidable cancer is related to tobacco use and therefore is preventable and that another 40 percent is related to nutrition and is also preventable. I don't think genetically determined cancers are the majority. Instead, most cancer is related to environment, to smoking, nutrition, physical activity and from changes to healthy cells that might be brought on by infections, such as the hepatitis viruses, human papillomavirus and Epstein-Barr virus, to name a few.
Read the companion interview with Dr. Abrams: Treating Cancer WIth Integrative Medicine.