Marijuana use is becoming more common as more states in the U.S. legalize it. Recent data shows that about 18% of Americans have tried marijuana at least once. But while its popularity grows, scientists are still working to understand its long-term health effects.
A new study from Northwestern Medicine has found that marijuana use might be linked to changes in our DNA, which could have important health implications.
Marijuana Use in the U.S.
Marijuana comes from the Cannabis sativa plant. People use it in different ways—smoking it in joints or bongs, drinking it as tea, or eating it in food.
In 2019, an estimated 48.2 million Americans used marijuana, making it the most commonly used drug in the country, according to the Centers for Disease Control and Prevention (CDC).
Despite its widespread use, scientists still don’t fully understand how marijuana affects the body. Some states have made it legal, but research on its long-term impact is still in its early stages. That’s why a team at Northwestern Medicine decided to investigate what marijuana might be doing inside our bodies.
What the Study Found
Dr. Lifang Hou, an expert in cancer research, led the study. The researchers analyzed blood samples from over 900 adults, taken five years apart. These individuals had already been part of an earlier study on heart health.
Participants were asked about their recent marijuana use, and scientists estimated how much they had used over their lifetime. Then, they examined their DNA for any unusual changes.
The researchers discovered differences in a process called DNA methylation in people who used marijuana. DNA methylation happens when small chemical groups attach to our DNA. These changes can turn genes on or off, affecting how cells work.
The study found between 16 and 132 DNA changes linked to marijuana use. Many of these changes appeared in genes related to:
- Cell growth
- Hormone signaling
- Immune system function
- Mental health conditions (such as schizophrenia, bipolar disorder, and substance use disorders)
What Does This Mean?
This study does not prove that marijuana causes these genetic changes. It also does not confirm that these changes lead to health problems. However, it suggests that marijuana could be influencing the way our genes work.
The findings raise important questions:
- Could long-term marijuana use increase the risk of certain diseases?
- Do these genetic changes affect different people in different ways?
- How might these changes impact health as people age?
Scientists need more research to fully understand these links. Future studies will help determine whether marijuana use directly leads to health risks or if other factors are involved.
Why This Research Matters
As marijuana becomes more widely accepted and legal in many places, it’s important to study its effects on the body. This research gives scientists a new direction for understanding how marijuana may influence our genes and long-term health.
For now, these findings highlight the need for more in-depth studies on marijuana and its potential impact on mental and physical health.
The study, led by Dr. Lifang Hou, was published in Molecular Psychiatry.
If you care about smoking, please read studies about smoking may increase heart disease risk by 200% and e-cigarette smoke may cause lung cancer and bladder disease.
For more health information, please see recent studies about the cause of weight gain after smoking cessation, and results showing smoking may cause white scars on the brain.
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