Men’s Fitness reported on a recent study done in the Netherlands that found Marijuana use does not significantly improve creative thinking. In fact, if you use it heavily, it significantly lessens divergent thinking.
In the test, researchers at Leiden University divided subjects into three groups of healthy current cannabis users. One group was given placebos, another group was given marijuana with the equivalent THC content of one joint, and the third group got marijuana with the equivalent THC content of three joints. None of the subjects were told the group they had been assigned.
Each participant was then required to complete a number of thinking tasks. They were given questions where they had to give the correct answer (convergent thinking) and problems to find new or creative approaches to solve (divergent thinking). The people who received the high THC content level marijuana were found to have significantly decreased ability for divergent or creative thinking. The other two groups were about equal in their ability to perform the tasks.
Other recent studies also reported on the Men’s Fitness site give even more bad news for chronic and long-term marijuana users.
In an unrelated 20-year study recently published in Addiction, marijuana isn’t just harmful to your cognitive (thinking) ability. But chronic (long-term) use can lead to schizophrenia and an increase in symptoms such as hallucinations and psychotic behaviors. Marijuana is also linked to reduced learning, memory, and attention issues. That’s not to mention that it has also proven to be addictive to some people. And the news just keeps getting worse since chronic marijuana users are also twice as likely to die from crashing their car.
Finally, in a study conducted at the University of Southern California with 455 men (163 with testicular cancer and 293 healthy), they found that recreational marijuana users had an increased chance of being diagnosed with testicular cancer germ cell tumors. This type of tumor is more difficult to treat and has a lower rate of recovery. The participants all answered questions about their use of tobacco, alcohol, and recreational drugs, as well as providing family history information. They found that those who smoked marijuana once a week for a 10-year period had double the chance of being diagnosed with the cancer in comparison to those in the study who didn’t ever use it. Or those who used it less than once a week for 10 years or less.
The idea for the cancer study came about because doctors and researchers began to see elevating rates of testicular cancer among men under 30.