Can a healthy diet help men with low-risk prostate cancer live longer? The authors of a new study say “yes.”
This new work, part of the long-running Physicians’ Health Study, suggests that a diet that is good for the heart, brain, and other parts of the body may also help keep low-risk prostate cancer at bay. On the flip side, a diet rich in red meat and high-fat dairy foods appears to be hazardous for men with this kind of cancer.
The new study involved more than 900 Physicians’ Health Study participants. Five years after being diagnosed with non-metastatic prostate cancer, they completed lengthy questionnaires about what they ate. Researchers then tracked their health for another 10 years. What the men ate fell into two distinct patterns: a “Western” diet heavy in processed and red meats, eggs, potatoes, high-fat dairy products, refined grains, and desserts; and a “prudent” diet weighted towards fish, poultry, plant-based protein, vegetables, fruits, whole grains, and salads.
The findings were published in this month’s issue of the journal Cancer Prevention Research.
Men whose diets scored highest in resembling the typical Western pattern had a 2.5-fold higher risk of dying from prostate cancer over the study period than men with the lowest Western pattern scores. They were also less likely to have died of any cause. Men with the highest prudent pattern scores were less likely to have died from prostate cancer or any cause.
In the Western pattern, processed meats such as salami, hot dogs, and bacon accounted for much of the increase in risk, while in the prudent pattern, the intake of olive oil and vinegar salad dressing contributed to the survival benefits. “The bottom line is that men with prostate cancer will benefit from the same diets recommended for preventing heart disease,” said the study’s corresponding author, Dr. Jorge E. Chavarro, assistant professor of nutrition and epidemiology at the Harvard T.H. Chan School of Public Health.
The study had some limitations. Nearly all the participants were Caucasian doctors, so the findings may not apply to men of other ethnicities, races, or socioeconomic backgrounds. In addition, the study didn’t account for the role of physical exercise or each participant’s personal history of PSA screening.
It isn’t clear why a diet that protects against heart disease would also protect against death from prostate cancer. Dr. Chavarro speculates that it’s because high-fat foods are easily broken down and absorbed by the digestive system, and so they might provide quick energy sources for growing tumors. Nevertheless, the results suggest that by eating healthily, men with prostate cancer can take a proactive step towards living a long life.
“This study adds to the expanding knowledge base that foods and diets that are heart-healthy may also be prostate-healthy,” said Dr. Marc Garnick, the Gorman Brothers Professor of Medicine at Harvard Medical School and Beth Israel Deaconess Medical Center, and Editor in Chief of HarvardProstateKnowledge.org. “The advice I give my prostate cancer patients is to avoid red meat, lots of dairy products, and vitamin E and selenium supplements. That has been my advice for years and the current findings support this approach.”