There is an epidemic of cancer today. One in three Americans will be diagnosed with cancer, often before the age of 65. I have been on the wrong side of this statistic since I was 31 years old, when I discovered I had brain cancer.
Since 1940, we have seen in Western societies a marked and rapid increase in common types of cancer. In fact, cancer in children and adolescents has been rising by 1 to 1.5 percent a year since the 1960's. And these are cancers for which there is no screening.
For most common cancers - prostate, breast, colon, lung - rates are much higher in the West than in Asian countries. Yet Asians who emigrate to the United States catch up with the rates of Americans within one or two generations. While in Asia, Asians are protected not by their genes, but by their lifestyle.
Indeed, modern studies show that at most 15 percent of cancers are due - and only in part - to inherited genetic defects. Eighty-five percent are not.
However, cancer does run in families: A landmark New England Journal of Medicine study showed that children adopted at birth by parents who died of cancer before the age of 50 had the cancer risk of their adoptive parents, not of their biological ones. What gets passed on from one generation to the next are cancer-causing habits and environmental exposures, not just cancer-causing genes.
We continue to invest 97 percent of our cancer research funds in better treatments and early detection. Only 3 percent is invested in tackling causes.
I was a founding board member of Doctors Without Borders, USA. I worked as a volunteer physician in Iraq, Guatemala, Tajikistan and Kosovo. I know about epidemics in refugee camps. No cholera epidemic can be stopped by early detection and antibiotic treatment - as effective and important as these are. That is because cases always develop at a rate faster than our ability to treat individual patients.
In the 1800s, Britain and America faced several large cholera epidemics. They were able to stop them without antibiotics. Scientists and physicians at the time had not even discovered the concept of germs, but leaders with enough foresight and concern decided to act on what seemed the most likely environmental cause: contaminated water sources in the neighborhoods with the most cases. Cholera receded.
It is ironic to think that if we had had antibiotics at the time, and had counted on them to deal with the disease as we count today on anticancer treatments, we might never have controlled cholera.
We have much more data about the most likely causes of the modern cancer epidemic than our forbears did about cholera.
The World Cancer Research Fund published a report in 2007 concluding that a majority of cancer cases in Western societies could be avoided with life-style measures: 40 percent from changes in diet and physical activity (more vegetables and fruits, less sugar, less red meat, regular walking or the equivalent activity 30 minutes six times per week), 30 percent from smoking cessation, and about 10 percent from reduced alcohol consumption.
We now even have data about how specific foods such as broccoli and cabbages, garlic and onions, green tea or the spice turmeric directly help kill cancer cells and reduce the growth of new blood vessels they need to develop into tumors.
Reducing exposure to many of the well-characterized chemical carcinogens abundant in our modern environments (pesticides, estrogens, benzene, PCBs, PVCs and bisphenol A from heating liquids in plastic containers, alkylphenols in cleaning products, parabenes and phthalates in cosmetics and shampoos, etc.) would contribute even further to lessen the cancer risk.
By neither discussing nor investing in research and preventive programs based on these established scientific facts, we are promoting a sense of hopelessness with respect to cancer.
Most people continue to view cancer as a form of genetic lottery when it clearly is not. While we should all guard against false hope in addressing cancer, we should guard even more adamantly against this false hopelessness. And we should begin to help our society, and each one of us, address the causes of this modern epidemic.
Dr. David Servan-Schreiber, clinical professor of psychiatry at the University of Pittsburgh and a founding board member of Doctors Without Borders, USA, is the author of "Anticancer - A new way of life."