Bad news for cannabis supporters. According to a new American study, marijuana use may lead to an increased risk of developing testicular cancer. The findings confirmed earlier studies which also showed links between cannabis use and testicular cancer.

For the study, published in the journal CANCER, researchers from the University of California conducted a case-control study of more than 450 men; 163 young men diagnosed with testicular cancer with about 290 healthy men of the same age.

They found men with a history of using marijuana were twice as likely to have a particular type of cancer usually occurring in younger men. However, while a two-fold increase in risk appears moderately strong, in absolute terms the increase in risk is small, amounting to 0.012% for all men in their late twenties. Surprisingly, the study also found that men with a history of cocaine use had a reduced risk of both subtypes of testicular cancer.

Testicular cancer is the most common cancer diagnosed in young men aged between 15 and 45. The study found a link with a type of testicular cancer that carries a somewhat worse prognosis than other types.