Marijuana, also known as cannabis, has become increasingly popular in the United States and many other parts of the world. As laws have changed, more people are using the drug for recreational and medical reasons.
According to the Centers for Disease Control and Prevention (CDC), about 48 million Americans, nearly one in five people, reported using marijuana in 2019. Despite its growing popularity and acceptance, scientists are still trying to understand how marijuana affects the body, especially after years of use.
Marijuana comes from a plant called Cannabis sativa. People use it in different ways. Some smoke it in hand-rolled cigarettes called joints or use water pipes known as bongs. Others consume it in foods, drinks, oils, or teas.
Many people believe marijuana is relatively safe because it comes from a plant and is now legal in many places. However, researchers say there is still much to learn about its long-term effects on health.
A recent study from Northwestern Medicine has provided new clues about what marijuana may be doing inside the body. The study was led by cancer researcher Dr. Lifang Hou and was published in the journal Molecular Psychiatry.
The research focused on whether marijuana use is linked to changes in DNA, the genetic material that carries instructions for how our bodies grow, develop, and function.
The researchers examined blood samples from more than 900 adults who participated in a long-term study of heart health. The participants provided blood samples on two occasions that were five years apart.
The scientists also collected information about the participants’ marijuana use, including how recently they had used it and how often they had consumed it over the years.
The research team focused on a process called DNA methylation. Although the name sounds complicated, it is actually a natural process that occurs in the body all the time. Small chemical groups attach themselves to DNA and can influence how certain genes work.
These changes do not alter the DNA sequence itself. Instead, they act somewhat like switches that can turn genes on or off or change how active they are. Scientists believe DNA methylation plays an important role in many aspects of health and disease.
The study found that marijuana users had between 16 and 132 differences in DNA methylation compared with people who did not use marijuana. Many of these changes appeared in regions of DNA involved in cell growth, hormone signaling, and the functioning of the immune system.
Some of the changes were also linked to pathways associated with mental health conditions, including schizophrenia, bipolar disorder, and addiction.
These findings are important because they suggest marijuana may affect the body in ways that are not immediately obvious. However, the researchers emphasized that the study does not prove that marijuana directly caused these DNA changes.
The research only found an association, meaning the two were linked. Other factors, such as lifestyle habits, environmental exposures, or genetic differences, could also play a role.
The study raises many new questions that scientists hope to answer in future research. For example, researchers want to know whether these DNA changes remain for many years or disappear after a person stops using marijuana.
They also want to learn whether these changes increase the risk of certain diseases, including heart disease or mental health problems. Another important question is whether different people respond differently to marijuana because of their genes, age, or overall health.
As marijuana becomes more widely available, understanding its long-term effects is becoming increasingly important. Some studies suggest marijuana may have potential benefits for certain medical conditions and symptoms. At the same time, this new research reminds us that marijuana may also have effects that scientists do not yet fully understand.
The publication of this study in Molecular Psychiatry marks another step toward understanding the complex relationship between marijuana and human health. Researchers say much more work is needed before clear conclusions can be drawn.
As new evidence emerges in the coming years, it may help individuals, doctors, and policymakers make more informed decisions about marijuana use and its possible effects on the body.
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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