Research conducted by scientists at Northwestern University highlights a significant connection between cannabis use and modifications in the epigenome, which governs gene expression in the human body. The study analyzed data from over 1,000 adults and found that cannabis consumption may lead to lasting changes in how genes function rather than altering the DNA sequence itself.
In this study, published in Molecular Psychiatry in 2023, researchers aimed to understand the implications of cannabis use on health outcomes. Epidemiologist Lifang Hou noted, “We observed associations between cumulative marijuana use and multiple epigenetic markers across time.” This finding is particularly relevant given that nearly half of all Americans have tried cannabis at least once, according to their research.
The investigation was rooted in a long-running health study that tracked participants from ages 18 to 30 over two decades. Individuals provided blood samples at the 15-year and 20-year marks, allowing researchers to measure changes in DNA methylation levels, a crucial aspect of epigenetic modification. Such modifications can affect gene expression without altering the underlying DNA structure, likening it to obscuring parts of a set of instructions.
By comparing blood samples taken five years apart, the team examined the epigenetic alterations of those who used cannabis either recently or over an extended period. They identified numerous DNA methylation markers associated with cannabis use, including 22 markers linked to recent use and 31 markers associated with cumulative use from the 15-year blood samples. At the 20-year point, they found 132 markers tied to recent use and 16 markers linked to cumulative use.
An interesting observation emerged when researchers consistently identified one specific marker previously associated with tobacco use, suggesting potential similarities in the epigenetic regulation between cannabis and tobacco consumption. The implications of these findings extend to various health concerns, with multiple epigenetic changes linked to conditions such as cellular proliferation, hormone signaling, and neurological disorders like schizophrenia and bipolar disorder.
While the study provides valuable insights into the relationship between cannabis use and epigenetic changes, it does not establish a direct causation between cannabis and adverse health effects. As Drew Nannini, another epidemiologist at Northwestern University, stated, “This research has provided novel insights into the association between marijuana use and epigenetic factors. Additional studies are needed to determine whether these associations are consistently observed in different populations.”
The findings underscore the necessity for further research into cannabis’s long-term health impacts, particularly regarding age-related health outcomes. As cannabis continues to gain acceptance and legal status across various regions, understanding its effects on human health remains paramount.
