Regular cannabis smokers have sex more often than non-users, research has claimed.
Previous studies have shown that heavy abuse of the drug can reduce male sperm count and cause erectile dysfunction.
But scientists now say that people who regularly smoke it have almost 20 per cent more sex on average.
Researchers questioned more than 50,000 people aged 25 to 45. Participants were asked how often they had sex in the last month and how frequently they had smoked cannabis in the past year.
The study at Stanford University in the US found that women who had not used cannabis in the last year had sex on average six times a month. But that rose to 7.1 times for those who smoked it daily.
Among men, non-users had sex 5.9 times against 6.9 times for daily users. The findings were published in the Journal of Sexual Medicine.
Study leader Dr Andrew Sun said: ‘Frequent marijuana use doesn’t seem to impair sexual motivation or performance. If anything, it’s associated with increased coital frequency.’
When cannabis users have been put into MRI scanners, there has been more activity in the right nucleus accumbens when they view erotic images.
This is the part of the brain which turns motivation into action, and has been linked with having sex more often.