Does Weed Lower Testosterone?

With its increased availability in both medical and recreational settings, weed use is on the rise. Consumers can purchase cannabis products legally at storefronts, like our EarthMed dispensary near O'Hare, in a matter of minutes.

According to the National Library of Public Medicine, men use cannabis more frequently and in higher quantities than women. As the CDC reports 48.2 million people using cannabis, one can assume there are a lot of men smoking weed or otherwise consuming cannabis. Considering there are that many men using marijuana, it’s important to start to think about the long-term effects of weed on men and medical cannabis users.

Since men aged between 18-25 have the highest rate of marijuana use, there is the possibility that smoking weed can affect testosterone levels. Lower testosterone in men can lead to many adverse effects, including weight gain, fatigue, gynecomastia, and even erectile dysfunction. Let’s examine weed and testosterone and if marijuana use affects testosterone at all. 

Testosterone and the Endocannabinoid System

To understand how weed and testosterone may be connected, we can look to answers from the endocannabinoid system (ECS). The ECS is a system that serves to regulate certain chemicals your body produces naturally and its receptors. THC’s effects on the ECS were discovered in the 1990s, and it turns out that endocannabinoid receptors also exist in the male reproductive system, including the testis, prostate, vas deferens, and spermatozoa. 

What does this mean for cannabinoids and testosterone production? Well, when it comes to THC and testosterone, a study on mice found that THC attaches itself to ECS receptors in cells responsible for healthy testosterone production. In these cases, this inhibited and lowered testosterone levels. But it is not exactly clear if effects like these also apply to humans.

Does Marijuana Lower Testosterone?

Marijuana’s status as a schedule 1 drug has made the research of its effects on humans challenging in the United States, but there have been studies conducted on animals. One recent study conducted on non-human primates confirms what other similar studies on animals have conclusively shown: cannabis use among male animals and primates seems to have negative effects by lowering testosterone levels, sperm count and quality, and decreased size in testes. 

One could expect these results to translate similarly to male humans, and to some degree, that seems to be the case. There have been studies linking weed use to lower testosterone levels, the most famous of which was conducted in 1974 by the New England Journal of Medicine. The study found that the average testosterone men aged 18-28 that did not smoke weed had an average testosterone level that was close to double the amount compared to men who smoked weed. However, another study conducted the same year found no correlation between weed use, at any amount, and testosterone levels in male humans. 

This points out that when it comes to human males, the jury is still out on whether or not weed lowers testosterone. 

Does Marijuana Increase Testosterone?

Contrary to previous studies, a clinical trial conducted in 1989 found there was no change in testosterone levels for men who smoke weed. In 2017, a survey conducted in the US on 1,500 men also found no noticeable difference in testosterone levels for men who smoked weed compared to men who never had. This helps to show that there is still not a consensus on weed and testosterone. In fact, some studies have indicated that smoking weed can actually have a positive effect on testosterone production. 

In 2017, in order to estimate the effects of marijuana and testosterone, a study in Denmark was conducted, which reported increased levels of testosterone in men. And in 2020, investigators from the University of Chicago conducted an analysis of data provided by the World Journal of Urology. In assessing the relationship between marijuana and testosterone, they found that “[M]en who reported smoking THC in the last year on average had a higher T (testosterone level) compared to those who did not report using THC.”

The Bottom Line

While it's known that THC has detrimental effects on testosterone levels in animals, these results do not readily apply to humans. And the limited research that has been conducted on human men does not seem to firmly support the theory that marijuana increases or decreases testosterone levels in men definitively.

With more US states legalizing marijuana, it’s critical for us to have a better understanding of the long-term effects of weed on men and testosterone levels. Pushing for marijuana legalization not only helps to decriminalize cannabis but also opens the path to much-needed research that can help us make the right choices for ourselves and our bodies.