A recent study published in the Journal of Clinical Endocrinology and Metabolism finds a connection between older men with low levels of testosterone and an increased long-term risk of death compared to men with normal testosterone levels. The study followed nearly 800 men, ages 50 to 91 years, who were living in a southern California community and who participated in the Rancho Bernardo Study during the 1980s. The men who were found to have total testosterone levels in the lowest quartile at the start of the study were 40 percent more likely to die over the next 18 years than those with higher levels. This difference could not be explained by age, illness, or lifestyle.

Assistant professor, Dr. Gail Laughlin, from the University of California San Diego notes, "This is the first report linking low levels of testosterone with earlier death in relatively healthy older men. We want to emphasize that this is an observational study and we cannot recommend that any man take testosterone based on these results. Only randomized clinical trials can determine whether testosterone supplements are safe and can promote longevity. In the meantime, lifestyle changes to prevent or decrease obesity may also extend longevity."

Low testosterone levels are often accompanied by symptoms such as low bone and muscle mass, increased fat mass, low energy, impaired physical, sexual, and cognitive function. Approximately 30 percent of men aged 60 years and older are afflicted with decreased testosterone levels.