Declining Desire May Lead to Lower Testosterone Levels
Lower levels linked to decreased sexual activity and desire, but not to fewer erections
FRIDAY, March 13, 2015 (HealthDay News) -- Experts have long assumed that as a man's testosterone level declines, so does his sex life. But a new study suggests the reverse may be true. The findings were presented recently at the annual meeting of The Endocrine Society, held from March 5 to 8 in San Diego.
David Handelsman, M.B.B.S., Ph.D., a researcher at the University of Sydney, and colleagues evaluated 1,705 men, age 70 and above, in Sydney. The researchers tested the men at the study's start and then again two years later, when the number of men in the study had dropped to 1,367. At both visits, the men answered questions about sexual functioning, including how often they were able to get and keep a viable erection, how often they had sexual activity that led to ejaculation (including masturbation and intercourse), and how much desire for sex they had compared to when they were 50.
The researchers also measured blood levels of testosterone and other hormones at both visits. They found that a decline in testosterone, although it was less than a 10 percent drop, was linked to decreased sexual activity and desire, but not to fewer erections.
"The reduction in sexual function was strongly associated with reduction in serum testosterone [levels] in our study," Handelsman told HealthDay. However, the decrease was small and other research has shown that it takes a 70 or 80 percent drop in testosterone to affect sexual functioning, he added. "So, the effect [of lower testosterone in the study] is too small to cause reduced sexual function, and it must be a cause or an effect, [so] it is mostly likely an effect [of less sexual activity]."