While an apple a day keeps the doctor away, an edible a day makes your testicles shrivel – at least, that’s according to a new report which found that ingestible cannabis slashed testosterone levels and ball size in rhesus macaques. While the association hasn’t been proven in humans yet, as fellow primates it potentially paints a worrying picture for testicular health in the face of chronic THC exposure.
Published in the journal Fertility & Sterility, the study is the first of its kind in assessing the impact of Delta-9-tetrahydrocannabinol (aka, THC) use on testicular function. They were looking at dosages that would reflect human substance use of ingestible cannabis, often referred to as “edibles”.
Operating from the Oregon National Primate Research Center at Oregon Health & Science University (OHSU), the team behind the paper used a non-human primate model, employing the help of rhesus macaques to observe if or how cannabis’s main psychoactive agent altered their reproductive health. Each monkey was given daily edibles over the course of seven months, using dosages which reflected human use and increased in alignment with their sperm cycles (how sperm is made is pretty fascinating, didn’t ya know?).
Analyses of the animals’ semen samples revealed that edibles proved to have a significant influence over the monkeys’ reproductive hormones, who were found to have much lower levels of testosterone and shrunken testicles.
“Our analysis of the collected samples found that THC use was associated with significant adverse impacts to the animals’ reproductive hormones, including decreased levels of testosterone and severe testicular shrinkage,” said senior author and associate professor of obstetrics and gynecology at OHSU School of Medicine Dr Jamie Lo in a statement.
“Unfortunately, these effects appeared to worsen as the THC dose was increased, suggesting a possible dose-dependent effect.”
Healthy levels of testosterone and happy, healthy testicle size are indicators of reproductive health, which has triggered concern among the authors that chronic exposure to THC could have significant ramifications for male fertility and reproductive outcomes.
“While more research is necessary to better understand the potential long-term impacts of THC in humans, these early findings are concerning from a clinical standpoint,” said lead author and associate professor of urology at OHSU School of Medicine Dr Jason Hedges.
“As the prevalence of edible marijuana use continues to increase in the U.S. and worldwide – particularly in males of prime reproductive age – even moderate doses could have a profound impact on fertility outcomes. While family planning may not be top of mind for those in their late teens and early 20s, the longer-term effects of THC on male reproductive health are not well-defined; it is possible that THC could cause lasting impacts that may alter family planning later in life.”