Marijuana is becoming more common in the United States as more states make it legal.
In 2019, about 48 million Americans said they used marijuana, according to the Centers for Disease Control and Prevention (CDC). That’s about 18% of the population.
Even though many people use marijuana, we still don’t fully understand how it affects our health in the long run. A new study from Northwestern Medicine gives us a better look at how marijuana might affect our DNA.
Marijuana comes from a plant called Cannabis sativa. People often smoke it in rolled-up paper (called joints) or use water pipes (called bongs). Some people also make tea with it or add it to food.
As marijuana becomes more legal and popular, people are asking more questions about its long-term health effects. That’s what the Northwestern team wanted to explore. The lead researcher, Dr. Lifang Hou, is a cancer expert.
Her team studied blood samples from over 900 adults who were part of an earlier study on heart health. These adults gave blood samples five years apart, and the researchers asked them about their marijuana use during that time—both recent and total use over their lifetime.
Then, the scientists looked at the participants’ DNA for changes. They focused on something called DNA methylation. This is when small chemical tags attach to your DNA and affect how your genes work—kind of like turning them on or off. The researchers found 16 to 132 parts of the DNA that seemed to be linked to marijuana use.
These DNA changes showed up in areas that help control cell growth, hormones, and the immune system. Some of the changes were also found in genes linked to mental health conditions such as schizophrenia, bipolar disorder, and addiction.
It’s important to understand that the study doesn’t prove that marijuana caused these DNA changes or that the changes will definitely lead to health problems. But the results do suggest a possible link that scientists need to study more.
This research shows that marijuana might affect how our genes behave, and that could affect our health over time. But we need more studies to know for sure how these changes affect us as we age, or if they increase our risk for things like heart disease or mental illness.
The study also raises other important questions. For example, do these effects show up the same way in different people? Could someone’s lifestyle or family history change the way marijuana affects their DNA?
As marijuana becomes easier to get and more people use it, learning more about its effects is very important. Some studies have suggested that marijuana might have benefits—like improving mood, helping older people feel better, or even protecting the brain as we age.
But this new study reminds us that marijuana affects the body in complex ways that scientists are still trying to understand.
This research, published in the journal Molecular Psychiatry, helps us take an important step toward understanding how marijuana might affect our health at a deep, molecular level. As more studies are done, we will be able to make better choices about marijuana, both as individuals and as a society.
If you care about cancer, please read studies that a low-carb diet could increase overall cancer risk, and berry that can prevent cancer, diabetes, and obesity.
For more health information, please see recent studies about how drinking milk affects the risks of heart disease and cancer and results showing vitamin D supplements could strongly reduce cancer death.
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