Can You Prevent Prostate Cancer?
This year more than 230,000 men in the U.S. will be diagnosed with prostate cancer and more than 30,000 will likely die from it. This makes it the most common cancer in men, as well as the number one cause of cancer death in non-smoking men. The death rate from prostate cancer in the U.S. is 5 to 10 times higher than it is in many developing countries in Asia or Africa. Even in Japan, the death rate from prostate cancer remains far lower than in the U.S., although it is rising as they adopt a more Western-style lifestyle.
However, African-Americans in the U.S. have the highest death rate from prostate cancer, and Asian-Americans appear to quickly lose their resistance to the disease when they move to the U.S. and adopt a more Western-style lifestyle. This means that genetic factors are unlikely to explain the very low rates of prostate cancer mortality in Asian and African countries.
Lowering Cholesterol Levels Reduces Cancer RiskBack in the 1970s, a study in Hawaii found that smokers with higher serum cholesterol levels had a much higher risk of developing lung cancer. In May 2005, a study of nearly a half million U.S. veterans was presented at the American Society of Clinical Oncology. The results showed that the development of lung, prostate, pancreatic and esophageal cancers was cut by about 50% in those taking statin drugs to lower their cholesterol levels. This data suggests a high-fat, Western diet rich in animal products may not only be promoting atherosclerosis, but may also be promoting the growth and spread of prostate cancer and likely other cancers as well.
Lifestyle Shown to Slow Progression of Prostate CancerIn the September issue of the Journal of Urology, a study of men with early prostate cancer proven by biopsy and PSA scores (ranging from 4-10ng/ml) were randomly assigned to one of two groups.The experimental, intensive lifestyle change group was placed on a very-low-fat vegan diet supplemented with fish oil, vitamin E, selenium and vitamin C. In addition, they walked 30 minutes a day, 6 days a week and underwent stress management techniques.The control subjects were instructed to follow standard medical advice. PSA levels fell modestly after one year in the experimental group but rose modestly in the control subjects. This same study, conducted by Dr. Ornish and others, also reported that the growth of a line of prostate cancer cells (LNCaP) was markedly inhibited in those in the experimental group, compared to those who received conventional medical treatment.1In 2001, a study at the Pritikin Longevity Center reported similar marked inhibition of the growth of prostate cancer cells grown in the serum of people who had followed the Pritikin program for just a few weeks. The diet was similar to Ornish study except for the inclusion of small amounts of fish and animal protein but without supplements. In this study, the serum of the participants before they started the study served as the control. The experiment serum was after they had been on the program for a few weeks.2 Serum cholesterol fell 20-30% on both the Ornish and Pritikin diets.It appears that a very-low-fat, near-vegetarian diet is likely to slow the progression of prostate cancer, at least in part because it lowers serum cholesterol levels. Growing evidence suggests that higher cholesterol levels in cell membranes can interfere with chemical signals for abnormal cells to self-destruct. This may promote the growth and spread of cancer cells in the body and help explain the much higher rate of prostate and other cancers in people consuming diets high in saturated fat and cholesterol.
Bottom Line: Very-low-fat, near-vegetarian diets markedly lower serum cholesterol levels and appear to regress atherosclerotic lesions in most people. Since most men who develop prostate cancer actually die from atherosclerotic disease, it seems reasonable to encourage men with early prostate cancer to adopt a very-low-fat, near-vegetarian diet. They should also be encouraged to get a little sunshine several days a week, as low levels of vitamin D also appear to promote prostate cancer.
By James J. Kenney, PhD, RD, FACN.References:1 J Urol. 2005;174:10652 J Urol. 2001;166:1185