Is Weed Really a Gateway Drug?

Marijuana—also known as cannabis or weed—is the most commonly used illicit recreational drug. It is often thought of as a soft drug, with proponents claiming that it is non-addictive and relatively harmless, particularly when compared with the much more available and socially acceptable drug, alcohol. Many people, though—parents especially—may worry about the common idea that marijuana is a gateway drug leading to harder and more addictive drugs.

Marijuana buds with marijuana joints
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The Gateway Drug Theory

The gateway drug theory states that so-called soft drugs, such as marijuana, provide an apparently safe psychoactive experience that makes naive users more open to experimenting with other, harder drugs.

Most people who develop severe problems with drugs, such as cocaine, meth, and heroin, had early experiences with marijuana before trying these other drugs.

However, it’s important to note that at the same time, most people who use marijuana will not go on to use these harder substances.

Nevertheless, the argument is that if these hard drug users had not taken marijuana in the first place, they would not have been lured into a false sense of security around drug use, and so would never have progressed to other, more harmful substances.

The Marijuana Legalization Debate

Marijuana has come a long way in its reputation for being a non-problematic substance, and even being beneficial in the context of medical marijuana. Despite this, some have argued that the biggest harm marijuana poses is its function as a gateway to other drug use.

By their exposure to illicit drug use in the form of marijuana, young people may be introduced to the world of drug use and to drug dealers who have other, harder drugs to offer, such as LSD, cocaine, and heroin.

Ironically, the gateway drug theory of cannabis has been used to support both sides of the debate on whether marijuana should be legalized. The anti-legalization lobby argues that marijuana's status as a gateway drug makes it more dangerous to users in the longer term, by introducing them to the experience of scoring, possessing, and consuming an illegal drug.

Meanwhile, the pro-legalization lobby argues that it is the illegal status of the drug, combined with its relative harmlessness, which makes it uniquely positioned as a gateway to other illegal drug use. They argue that if marijuana were legal, it would no longer be a gateway drug, as users could purchase the drug through legal channels and thus not be exposed to harder drugs.

Is Marijuana Harmless?

The relevance of the gateway drug theory rests on the premise that marijuana is harmless, which is incorrect. But this does not provide much support for the argument that marijuana is not a gateway drug.

To make that argument, it would have to be admitted that marijuana is potentially harmful in its own right, and the anti-legalization movement could then simply shift their emphasis to the direct harms caused by marijuana.

As this does not support the goals of the pro-legalization side, proponents tend to stick to the view that marijuana is, for all intents and purposes, harmless, and the harms it causes arise from its illegal status.

Does Marijuana Lead to Other Drug Use?

Extensive research into the relationship between cannabis use and other drug use has only partially answered this question. Studies indicate that some people have a partially genetic predisposition to drug use and that they are more likely to become heavy cannabis users. However, this finding doesn't particularly support the view that exposure to cannabis leads to other drug use.

The social aspects of the gateway drug theory are supported by evidence that cannabis users socialize with drug-using peers in settings that provide more opportunities to use other illicit drugs at an earlier age, and that this forms an illicit drug subculture with positive attitudes toward the use of other illicit drugs.

The Gateway Theory Cannot Be Proved

The actual prevalence of drug use is impossible to measure, and studies of drug use are fraught with inaccuracies, so there is no way of knowing whether marijuana and use of other drugs are consistently related. Certainly, there are many people who use marijuana and do not progress to other drug use, as well as many who do.

Even if it was proven that users of marijuana were significantly more likely to use other drugs, there is no way of knowing whether it was because of the gateway role of marijuana, whether there were other factors at play, or because the individuals involved simply used whichever drugs were available to them.

A Word From Verywell

Don't automatically assume that someone you know will progress to other drug use after using marijuana. But don't ignore the possibility, or assume that marijuana use won't lead to problems. It is important that parents take steps to prevent addiction in their kids, especially by setting appropriate boundaries, such as no smoking in the home. Additionally, parents should be willing to support a child in seeking help if needed.

13 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Pew Research Center. In Debate Over Legalizing Marijuana, Disagreement Over Drug’s Dangers.

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  4. Centers for Disease Control and Prevention. Risk of Using Other Drugs.

  5. National Institute on Drug Abuse, NIH. Is Marijuana a Gateway Drug?

  6. Harvard Medical School Harvard Health Publishing. Medical marijuana.

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  8. Marijuana Policy Project. Effective Arguments for Legalizing and Taxing Marijuana.

  9. Centers for Disease Control and Prevention. Marijuana: How can it affect your health?

  10. CATO Institute. The Effect of State Marijuana Legalizations: 2021 Update.

  11. National Institute on Drug Abuse, NIH. Genetics: The Blueprint of Health and Disease.

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  13. National Institute on Drug Abuse, NIH. Cigarette Smoking Increases the Likelihood of Drug Use.

Additional Reading
Elizabeth Hartney, PhD

By Elizabeth Hartney, BSc, MSc, MA, PhD
Elizabeth Hartney, BSc, MSc, MA, PhD, is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada.