Use of Marijuana Increases Cancer Risk

Cannabis (marijuana) damages the immune system, increasing vulnerability to breast, bladder, lung and other tumors, as well as bacterial infections such as Legionnaires disease, according to a new study. Researchers at the University of South Carolina found that THC, the chemical behind the “high” of cannabis, fueled the production of a flood of cells thought to weaken the body’s built-in defenses. In tests on mice, THC triggered the production of a “massive” number of immune cells called myeloid-derived suppressor cells (MDSCs), which normally act as a safety brake on the immune system, stopping its battle against disease from spiraling out of control. But, in the case of cancer, MDSCs make it easier for tumors to grow.

According to the researchers, the findings could have important implications not only for those who use the drug recreationally, but for those taking it to improve their health. Cannabis is used to ease the symptoms of multiple sclerosis, and it can also be used in treatment of cancer, glaucoma and HIV. However, a greater understanding of how to weaken the immune response could lead to new treatments for diseases caused by the immune system turning on the body.