More weed, more problems? As in, if you smoke all day, everyday, your life is likely a hot mess with no hope of redemption? According to recent research from CU Boulder, the answer to “more weed, more problems” is no.
According to researchers, legalizing recreational cannabis at the state level does not lead to an increase in substance use disorders. Or even increased use of illicit drugs among adults. In fact, it may even decrease issues related to alcohol abuse.
A study involving over 4,000 twins from Colorado and Minnesota found no correlation between cannabis legalization and any increases in cognitive, psychological, social, relationship, or financial problems.
“We really didn’t find any support for a lot of the harms people worry about with legalization,” said lead author Stephanie Zellers. “From a public health perspective, these results are reassuring.”
The study, published in Psychological Medicine, was conducted by researchers from the University of Minnesota, CU Boulder and the CU Anschutz Medical Campus. The study used data from two of the nation’s most extensive and longest-running twin studies: one located at IBG and the other at the Minnesota Center for Twin Family Research.
What Are Twin Studies?
Can twin studies prove that more weed doesn’t equal more problems? Well, what are twin studies?
Twin studies are research designs that compare identical (monozygotic) and fraternal (dizygotic) twins. The idea is that identical twins share all their genes, while fraternal twins share only about half of their genes.
So any differences between the two types of twins can help researchers identify which traits or conditions are likely influenced by genetics and which are likely influenced by environment. Researchers can use twin studies to study a wide range of topics, including genetics, development, and health.
IBG stands for Institute of Behavioral Genetics, a research center at the University of Colorado Boulder. The Minnesota Center for Twin Family Research located at the University of Minnesota.
Both centers conduct twin studies and have been collecting data over the years. And both centers are among the nation’s most prominent and longest-running twin studies. They provide researchers with a wealth of data on genetic and environmental factors related to human behaviour and development.
The Problem with The Studies
Of course, Twin studies are not without their critics.
- Assumption of equal environments: Twin studies sometimes assume that identical and fraternal twins are raised in similar environments, but this may not always be the case. For example, identical twins may be treated more similarly than fraternal twins, which could affect the results.
- Limited generalizability: Researchers often conduct twin studies on small, specific samples, such as twins from a particular country or region. This limits the generalizability of the findings to other populations.
- Missing heritability: Twin studies estimate the proportion of variation in a trait or condition due to genetics. But they do not account for all the genetic variation that may influence the trait or condition.
- Complexity of human behaviour: Many complex human behaviours and conditions, such as mental disorders or intelligence, likely result from multiple genes and environmental factors. Twin studies may not fully capture these interactions.
- Selection bias: Twins who volunteer for studies might differ from twins who do not volunteer, which can bias the results.
Twin Studies Disprove More Weed, More Problems?
The researchers of this “more weed, more problems” study compared the 40% of twins who reside in states where recreational cannabis is legal to those who live in states where it remains illegal to understand the overall impact of legalization.
Researchers have been tracking the participants, who are now between the ages of 24 and 49, since their adolescence. They’ve been gathering information on their use of alcohol, tobacco, cannabis and several other illicit drugs, as well as assessing their overall well-being.
By specifically comparing twins within 240 pairs, in which one twin lives in a state with legal cannabis and the other where it is not, the researchers aimed to identify any changes caused by cannabis legalization.
The researchers previously found that identical twins residing in states where recreational cannabis is legal tend to use it around 20% more often than their twins living in states where it remains illegal.
So does that mean more weed, more problems?
To answer this question, the team compared survey results that examined 23 indicators of “psychosocial distress.” Including the use of alcohol and illicit drugs like cocaine and heroin, psychological distress, financial difficulties, cognitive issues, unemployment, and relationship issues both at home and at work.
“We included everything we had data on with the goal of getting a well-rounded look at the impacts on the whole person,” said Zellers. “Big picture, there’s not much there.”
No, More Weed Does Not Equal More Problems
So is “more weed, more problems” debunked?
Researchers found no relationship between legal cannabis and an increased risk of “cannabis use disorder” or dependency.
For years, critics have called cannabis a “gateway” drug to harder substances like cocaine and heroin. The researchers found no changes post-legalization.
“For low-level cannabis use, which was the majority of users, in adults, legalization does not appear to increase the risk of substance use disorders,” said co-author Dr. Christian Hopfer.
Not only does this study question the “more weed, more problems” narrative, but it also shows legal cannabis’ benefit. People in legal states are less likely to develop alcohol dependency problems, including driving drunk.
“Our study suggests that we should not be overly concerned about everyday adult use in a legalized environment. But no drug is risk-free,” said John Hewitt, professor of psychology and neuroscience at CU Boulder.
While the study found no adverse effects on the daily lives of cannabis-consuming adults, the study also found no evidence that legal cannabis benefited people’s cognitive, psychological, social, relationship, or financial status.
Overall, the study seems to suggest the same thing we have before. Substances are neutral. It is the person who can choose to use or abuse them. But the drugs themselves have no innate power of control.