Healthy Living May Reduce Risk of Severe Prostate Cancer By Over Half

Avoiding Prostate Cancer

Stacey Kenfield, ScD

Living a healthier lifestyle could be a robust preventative measure against metastatic prostate cancer. A study¹published by a team of researchers from both the University of California, San Francisco (UCSF) and Harvard discovered that exercise and other healthy lifestyle habits may decrease a man’s chances of developing lethal prostate cancer by up to 68%.

The researchers analyzed data from two US studies to determine whether or not lifestyle changes produce life-saving benefits. They awarded a “point” for every affirmative response to lifestyle changes study participants incorporated into their daily life. For example, researchers assigned one point to a participant for every affirmative response to questions such as if they practiced regular, intense exercise, had a body mass index under 30, and were tobacco-free for a minimum of 10 years. These questions also included diet-related questions, such as if they had a high intake of fatty fish and tomatoes, and a low intake of processed meat.

The first collection of data originated from the Health Professionals Follow-Up Study, which tracked nearly 42,000 men between the ages of 40 and 75 during a 14-year period from 1986 to 2010. The second set of data, the Physicians’ Health Study, examined 20,000 men between the ages of 40 and 84 during an even longer time frame, from 1982 to 2010.

The team discovered that participants who accumulated 5 to 6 points in the Health Professionals survey had a 68% of decreased risk for lethal prostate cancer. Comparatively, 38% demonstrated a decreased risk in the Physician’s group.

The research team identified 576 cases of lethal prostate cancer in patients observed throughout the Health Professionals study, and 337 cases participating in the Physicians study.

“It’s interesting that vigorous activity had the highest potential impact on prevention of lethal prostate cancer. We calculated the population-attributable risk for American men over 60 [years] and estimated that 34% of lethal prostate cancer would be reduced if all men exercised to the point of sweating for at least 3 hours a week,” said lead author Stacey Kenfield, ScD, assistant professor, Department of Urology, UCSF Medical Center, in a statement.

Kenfield added that incorporating five or more of these health habits could help decrease the number of lethal prostate cancer cases by almost half in men over the age of 60.

Not all cases of prostate cancer metastasize and become life-threatening according to the study — only a minority of patients are diagnosed with the aggressive, fatal form of the disease. Regardless, prostate cancer has still become one of the most frequently diagnosed cancers in the United States.  

Additionally, controlling one’s diet alone showed its own benefits in decreasing risk for this lethal prostate cancer. For example, men observed in the Health Professionals study showed a 46% decreased risk of developing the disease if they scored 3 or more points in affirmative dietary choices.

“This study underscores the ongoing need for more effective prevention measures and policies to increase exercise, improve diet quality, and reduce tobacco use in our population,” said senior author June M. Chan, ScD, departments of Urology, Epidemiology, and Biostatistics, UCSF, in a statement.

“It takes cooperation and effort from multiple areas, like insurance companies, employers, policy makers, and city planners, to figure out how to creatively support and encourage more exercise into most busy adults’ working day.”

Patients observed in the studies had to be free of cancer at the start of the study. Researchers also imposed a 4-year lag period to rule out any participants who may have unknowingly developed the lethal prostate cancer, all as a means to reduce error over the nearly 20-year long studies.

Reference

1. University of California. Working up a sweat may protect against lethal prostate cancer. http://universityofcalifornia.edu/news/working-sweat-may-protect-against-lethal-prostate-cancer. Accessed December 3, 2015.