Gateway drug theory

The gateway drug theory unproven hypothesis is an assertion that the use of "softer" drugs will lead to the use of "harder" drugs. A commonly assumed pattern is that alcohol or nicotine use will lead to marijuana use, followed by cocaine, methamphetamine, or heroin use, in a manner similar to a slippery slope. Another variation posits that some dealers will spike their supplies of marijuana with the harder drugs, so as to get their customers addicted to the latter before they know they are using them (although most dealers have little reason to do this, as they would be losing money by selling more expensive drugs for the price of marijuana).
== Conflicting studies ==
Studies on the gateway drug theory show conflicting results;Andrew R. Morral, Daniel F. McCaffrey & Susan M. Paddock. Reassessing the Marijuana Gateway Effect Addiction vol 97(12), 2002; pp.1493-1504 some studies support the concept while others bring it into question. One RAND Corporation study failed to identify a significant gateway effect in the case of marijuana. RAND speculated that a common-factor model, in which certain factors (genetic, environmental, social, etc.) determine the likelihood of a particular subject engaging in the use of particular drugs (the "common-factor model"), is another possibility. Hence, it may be a case for which correlation does not equal causation. A large, multifaceted 2017 literature review of marijuana found moderate evidence for a correlation between marijuana use and "the development of substance dependence and/or a substance abuse disorder for substances including, alcohol, tobacco, and other illicit drugs", but could not find enough evidence to address the issue of causation.The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research by Committee on the Health Effects of Marijuana: An Evidence Review and Research Agenda; Board on Population Health and Public Health Practice; Health and Medicine Division; National Academies of Sciences, Engineering, and Medicine (2017) The National Academies Press. ISBN 978-0-309-45304-2.
== Crank arguments ==
The theory may reflect a mental model based on the increasing availability of certain drugs, particularly since alcohol and nicotine are legal. If, for example, one drinks alcohol 250 times and smokes marijuana 20 times over the course of 5 years, one is more likely to have used alcohol first.Earleywine, Mitch. "Stepping-Stones, Gateways, and the Prevention of Drug Problems." Understanding Marijuana, A New Look at the Scientific Evidence. Oxford: New York, 2002, 49-66. Notably, few people claim that caffeine or (most) proper use of pharmaceuticals causes the use of other drugs.
There is little physiological reason to assume that one drug acts as a gateway to others, as different neurological receptors are involved with different drugs, although most psychoactive drugs do result in an increase in the amount of dopamine in the brain.
Proponents of the gateway drug theory may use statistics in a misleading manner, for example citing studies showing a high percentage of heroin users had previously used cannabis, in an effort to imply causation. They likely had been previously exposed to caffeine as well, but that is not mentioned. Even if it was established that 100% of heroin users had previously used marijuana, it would not follow that their marijuana usage was a causative factor in their progression to heroin, nor does it prove that 100% of marijuana users (or even a statistically significant percentage of marijuana users) later used heroin. 
There is an argument that the prohibition of marijuana can lead users to buy from people who may also sell other drugs, or at least become comfortable with the modes and nature of the underground drug distribution system, but this is actually a reason to legalize cannabis. The same hypothetical effect would be seen if hamburger users were forced to buy their patties on street corners and in back alleys.
There is another argument that, since cannabis is illegal, it has a certain "taboo" mystique about it. When a curious young soul finally works up the courage to try this "criminal substance," he might discover that the effects are far less impressive than the mystique and social guidance films about marijuana like Reefer Madness suggest. This, in turn, might make him wonder just how bad other equally illegal drugs are (though, at least under federal law in the United States, some "hard drugs" like methamphetamine and cocaine are actually i.e., have fewer federal restrictions, than marijuana).
At least two studies, including one published by the University of Pittsburgh in 2006,"Study says marijuana no gateway drug", ScienceBlog.com, 4 December 2006. and another published by the University of New Hampshire in 2010,"Risk of marijuana's 'gateway effect' overblown, research shows", PhysOrg.com, 2 September 2010. show that stressors like unemployment play a bigger role in the use of progressively harder illicit drugs.
==See also==
*Gateway religion
==References==
Category:Drugs
Category:Pseudoscience