Prostate cancer is the second most common cancer in men and many have felt that taking natural supplements could help stave off the progression of the disease. However a new study out of Canada finds that ingesting vitamin E, selenium and soy for example serve as no benefit to men who were at a higher risk of developing the disease.
In this study, the researchers assigned 303 men to take either a combination of the supplements or a non-nutritive powder that resembled the supplements every day for three years. When comparing the number of cases of cancer in each group after three years, the results were nearly identical. Twenty-six out of every 100 men developed prostate cancer after three years, regardless of whether they took the supplement or the placebo powder.
Dr. Neil Fleshner, who worked on the new research and heads the urology department at the University Health Network in Toronto frankly states:
"To our chagrin, there was no benefit. We need to look at new strategies and novel nutritional agents."
Vitamin E and selenium are both antioxidants that are present in foods. All the men had signs of pre-cancerous cells, which put them at a higher risk for developing prostate cancer.
The current research differed from previous work in that it included soy. Fleshner said rates of prostate cancer are much lower in China and Japan, where people consume soy in large amounts, than in the United States or Canada. The results don't rule out that soy might be beneficial to those who eat it frequently for decades, but three years of extra soy don't appear to help prevent prostate cancer.
In a study published in October 2004 by the Urological Sciences Research Foundation found that when Japanese men migrate to the United States and adopt a Western lifestyle, the soy protection against prostate cancer begins to disappear within one generation. The researchers suggested that the western diet containing high animal saturated fats and low soy content may be the contributors to the higher incidences of prostate cancer.
Many people often associate the benefits of soy with breast cancer. Indeed, data on soy and prostate cancer has been most promising; many studies support the role of soy in the prevention and possible treatment of prostate cancer. During the late 80s, researchers found that Japanese men in Hawaii who ate tofu at least 5 times per week had 65% less chance of developing prostate cancer than those who ate tofu only once a week or less. In 1998, researchers found that men who drank soy milk at least once a day had a 70% less chance of developing prostate cancer than those who never drank soy milk at all.
Dr. Eric Klein, chair of the Glickman Urological and Kidney Institute at the Cleveland Clinic concluded:
"I think that in the absence of more compelling scientific data for vitamin E and selenium, that we should move on."
Prostate cancer is diagnosed in 156 out of every 10,000 men in the United States each year. However, some of the tumors may never become deadly and there is ongoing debate over the best way to treat them.
Sources: The Journal of Clinical Oncology and The Urological Sciences Research Foundation
Written by Sy Kraft