It’s not unusual for people to joke about guys who smoke weed being pretty useless in bed, but is there any connection between the male sex drive and his pot habit, or is this simply an urban myth? Could problems getting it up or staying hard be more about being chilled out than a sign of something sinister? And if smoking marijuana really does cause a man’s testosterone levels to drop so far he can’t function properly in the bedroom is that a temporary issue, or something that could last for many months or years ahead? This topic raises lots of serious questions that all men who smoke weed really need to know the answers to.

What is testosterone?

Basically put – it’s a sex hormone which both males and females have in their bodies, although men (generally) have a lot more. Amongst other things it regulates a man’s sex drive and sperm production, as well as being in charge of things like muscles. A small percentage of every man’s testosterone is naturally changed into estrogen – a typically ‘female’ hormone, but this is perfectly natural, indeed vital for a man to enjoy full erections and have a healthy libido.

How does cannabis affect a male hormonal system?

It’s THC, the active chemical that weed contains, which plays havoc with the human body; in this case it lowers the production levels of two hormones in the endocrine system, which in turn causes testosterone levels to drop. During one study blood tests on male monkeys which were given just 5mg of marijuana showed a 65% decrease in their testosterone results compared to the base readings. This effect lasted for three days afterwards.

Another possible connection is that made between marijuana and the stress hormone cortisol – which by its nature reduces the body’s testosterone levels, and consequently your sex drive. Smoking marijuana is thought to boost cortisol production, which would in turn further decrease testosterone levels. Many people may worry about the effects of weed while exercising, the affects of taking the substance before or after working out would boil down to a potential hormone imbalance.

Do men risk developing female features like breasts?

This is a highly debated topic with no clear answers. Experiments on animals suggest it is highly likely, but similar studies on humans are less conclusive. It’s probably best to say it’s a calculated risk, but bear in mind that there’s plenty of evidence that regular use of marijuana leads to shrinking testicles, lower sperm count, and even delayed puberty. Some studies suggest this could be because changing testosterone levels inevitably change the percentage of estrogen in the body.

Do all marijuana users run the same risks?

Current research suggests that very occasional weed smokers run a much lower risk of affecting their testosterone levels, and consequently regular consumption raises the risk accordingly. As it takes around one full day for the body’s natural testosterone levels to stabilize after consumption, those who have at least one joint a day are likely to be affected on a quasi-permanent basis. It would be naïve to claim that smoking marijuana has no negative effect on a male’s testosterone levels, and only further studies can possibly reveal the long term effects of such actions.