Men with naturally high concentrations of testosterone in their blood face an elevated risk of prostate cancer, according to data collected since 1961. If testosterone concentrations that have been artificially elevated carry the same danger, then men who use hormone supplements to combat age-related problems could be in for trouble, says a group of Baltimore researchers.
J. Kellogg Parsons of Johns Hopkins Medical Institutions in Baltimore and his colleagues used nearly 40 years of test results from 794 men to assess the relationship between prostate cancer and variations in blood concentrations of testosterone. All the volunteers were healthy and living in Baltimore when they joined the study decades ago, and each underwent multiple testosterone tests.
The scientists found that men with the highest concentrations of what's known as free testosterone were 2.6 times as likely to get prostate cancer as were men with the lowest concentrations of that sex hormone.