Marijuana use is becoming more common, especially as laws change and more places allow it for medical or recreational use.
In the United States, recent data shows that nearly 1 in 5 adults have tried marijuana at least once. As more people use it, scientists are working hard to understand how it affects the body, not just in the short term, but over many years.
A new study from Northwestern Medicine, published in the scientific journal Molecular Psychiatry, has provided an important clue. The research suggests that marijuana use may be linked to changes in the way our genes work. This finding could help explain some of the long-term health effects that people have reported.
Marijuana comes from the Cannabis sativa plant. People use it in different ways. Some smoke it in joints or pipes, while others eat it in food products or drink it in teas. Because it can create a feeling of relaxation or euphoria, it is popular for both recreational and medical use.
According to the Centers for Disease Control and Prevention, tens of millions of people in the United States use marijuana each year. Even though it is widely used, many questions remain about how it affects the body over time. This is why scientists are now studying its effects more closely, including how it may influence our DNA.
In this study, researchers led by Dr. Lifang Hou looked at blood samples from more than 900 adults. These participants had already taken part in a long-term study on heart health. The scientists had access to blood samples taken at two different times, about five years apart. This allowed them to see how things changed over time.
The researchers asked each person about their marijuana use. They wanted to understand both recent use and how much marijuana each person had used over their lifetime. Then, they examined the DNA in the blood samples to look for any changes.
They focused on a process called DNA methylation. This is a natural process where small chemical tags attach to DNA. These tags do not change the DNA itself, but they can turn genes on or off. In simple terms, they help control how the body uses genetic information.
The results showed that marijuana use was linked to changes in DNA methylation. The researchers found between 16 and 132 markers in the DNA that were different in people who used marijuana compared to those who did not.
These markers were found in genes related to important body functions. Some were linked to how cells grow and develop. Others were connected to hormone systems, the immune system, and brain health. Some of the affected genes have also been linked to mental health conditions such as schizophrenia, bipolar disorder, and substance use disorders.
It is important to understand what this study does and does not show. The research does not prove that marijuana directly causes these DNA changes. It also does not prove that these changes lead to disease. However, it does show a clear connection between marijuana use and changes in how certain genes may be regulated.
This raises important questions. For example, could long-term marijuana use affect the risk of certain health conditions? Could these changes help explain why some users experience mental health issues or immune problems? Scientists do not yet have clear answers, but this study provides a starting point for future research.
The findings are important because they suggest that marijuana may affect the body in deeper ways than previously thought. Instead of only affecting the brain for a short time, it may also influence how genes behave over longer periods.
As marijuana becomes more accepted and widely used, understanding these effects becomes even more important. People often see it as natural and safe, but “natural” does not always mean harmless. Learning more about its long-term impact can help people make better decisions about their health.
The researchers say their work may guide future studies, especially in areas like mental health, aging, and chronic disease. Scientists may now look more closely at whether these DNA changes are linked to conditions such as depression or Alzheimer’s disease.
This study is not the final answer, but it is an important step forward. It shows that marijuana use may be connected to real biological changes inside the body. As research continues, we will gain a clearer understanding of what these changes mean.
For now, this research reminds us that it is important to stay informed. As marijuana use continues to grow, understanding both its benefits and risks will help people make safer and more thoughtful choices.
If you care about cannabis, please read studies that what you need to know about cannabis and heart attack, and CBD from cannabis may help inhibit COVID-19 infection.
For more information about cannabis, please see recent studies that medical cannabis could help reduce depression, and results showing this stuff in cannabis may protect aging brain, treat Alzheimer’s.
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