Numerous studies have now shown that people who use cannabis have a higher likelihood of experiencing mental health problems. The potency of the drug – and how often it’s used – are likely to play a role in this relationship. Different types of cannabis have different levels of a component called tetrahydrocannabinol (THC). “High potency” cannabis has higher amounts of THC. Our recent study compared people who said they used high potency cannabis with those using lower potency cannabis. We found that the people who used high potency cannabis were more than four times as likely to report symptoms of cannabis misuse, and almost twice as likely to report anxiety disorder. (See also: Can we make cannabis safer?)