Do most people who use marijuana go on to other drugs? No. But do most people who use other drugs start with marijuana? Most definitely.
A wide array of research has confirmed links between marijuana use and other drugs. While it is true most marijuana users won’t go on to use other drugs, research demonstrates that 99% of those addicted to other drugs started with alcohol and marijuana. Marijuana users are also three times more likely than non-users to become addicted to heroin, and a 2017 National Academy of Sciences report found a statistical association between marijuana use and the development of substance dependence for other drugs like opioids and heroin.
It’s also important to keep in mind that marijuana on its own is harmful. The average potency of marijuana has skyrocketed since the 1970’s and research demonstrates it is associated with substance use disorders, drugged driving crashes, lower IQ, and other negative consequences. Today, more young people are voluntarily seeking treatment for marijuana addiction than for all other drugs combined, including alcohol.