At age 31, I was an ambitious physician and neuroscience researcher who reveled in discovery and glittering science projects. Then, slipping into a brain scanner one evening to take the place of a study subject who hadn't shown up, I was suddenly stripped of my white-coat status and thrown into the gray world of patients. The scan revealed a brain tumor that turned out to be cancer.
Being a physician didn't protect me from cancer, but it allowed me to dig deeply into the medical literature in search of ways to live longer than the few years I was expected to survive.
The first thing I learned is that we all carry cancer cells in us, even if only a few. But we also have natural defenses that usually prevent these cells from becoming an aggressive disease. These defenses include our immune system; the bodily functions that control inflammation; and foods that reduce the growth of blood vessels needed by tumors.
More than one third of Americans will develop detectable cancer. But nearly two thirds will not; their natural defenses will have kept the disease from taking hold. To survive my brain cancer, I knew, I'd need to learn how to strengthen my own protective systems.
In far too many Americans, these defenses are breaking down. Cancer rates increased steadily for decades before beginning a slight decline in recent years. And cancers that have no screening test—lymphomas, and pancreatic and testicular cancers, for example—are still rising. While the aging of the population plays a role, it is not the sole cause: cancer in children and adolescents rose at a rate of 1 to 1.5 percent per year during the 30 years ending in 1999. Asian countries have not experienced the same trends. Yet within one or two generations, Asian Americans get some cancers at rates similar to those of Caucasian Americans.
This tells us we don't get cancer by genetic lottery alone. A study in The New England Journal of Medicine conducted by the University of Copenhagen found that people who were adopted at birth had the cancer risk of their adoptive parents rather than that of their biological parents. At most, genetic factors contribute 15 percent to our cancer risk. What determines the other 85 percent of our risk is what we do—or do not do enough of—with our lives.
When it comes to surviving cancer once it is diagnosed, there are no proven substitutes for conventional treatments: surgery, chemotherapy, radiotherapy, immunotherapy, or, soon, molecular genetics. But these treatments target the tumor much as an army wages war: by killing enemy cells. They do not help prevent the disease, and they do not help keep it from coming back.
For prevention or better disease management, it is important to change the environment—the "terrain"—that surrounds cancer cells. Research suggests that cancer grows much faster under three circumstances:
- When our immune system is weakened and less capable of detecting and destroying budding tumors;
- When low-grade chronic inflammation in our body supports the invasion of neighboring tissue;
- When tumors are allowed to develop new blood vessels to feed growth.
When we strengthen our immune system, reduce inflammation, and reduce the growth of new blood vessels, we help create an anticancer terrain. And, increasingly, research demonstrates the lifesaving results. At Ohio State University, for example, a team followed women with breast cancer who all had surgery and conventional treatment. Some participated in an education group focused on better nutrition, more exercise, and simple stress reducers such as "progressive relaxation," in which participants lie down and consciously loosen their muscles. Those who learned to change their lifestyle were half as likely to die from their cancer during the 11-year study as those who did not. This research shows that lifestyle choices can transform the body's ability to resist cancer.