As recreational marijuana becomes increasingly legal in the United States, researchers become more interested in knowing the side effects of tetrahydrocannabinol (THC). The chemical is the active ingredient of cannabis responsible for most of its psychological effects.
Effects Of THC On Men's Sperm Cells
Findings of a new study now reveal that THC in weed may have serious impact on men who are in their childbearing years as this could leave effects on their sperm and possibly their children who conceived at the time they are using the drug.
In the study published in the journal Epigenetics on Dec. 19, Susan Murphy, from Duke University Medical Center in North Carolina, and colleagues found that higher concentration of THC in the urine is associated with a lower sperm count.
They also found that those who smoke weed had changes in their sperm genetic profile, which in other studies, have been linked to abnormal growth and cancer.
Earlier studies have already shown that smoking pot can lower sperm count but the new study is the first to provide evidence of a strong correlation between THC concentration in men's urine and the amount of the viable sperm.
The study showed that sperm concentration in the semen of non-marijuana users was about twice higher than those who smoke pot.
The researchers also found that THC changes how genes work in sperm cells.
The body has chemical tags known as methyl groups that get added to the DNA and regulate gene expression. While this is considered a normal process, it can be influenced by environmental factors. Researchers found these so-called epigenetic changes among pot users.
"We found enrichment of altered CpG sites associated with genes involved in the Hippo signaling pathway and in Pathways in Cancer, findings that were replicated in THC-exposed rodents," the researchers wrote in their study.
"These results indicate that the major epigenetic effect of cannabis exposure may be due to the THC component."
Effect On Offspring
The researchers, however, could not determine if the changes in sperm may have an effect on the fertilization processes and the health of the weed user's offspring. The researchers nonetheless advise caution.
"In the absence of a larger, definitive study, the best advice would be to assume these changes are going to be there [in sperm]," Murphy said. "I would say, as a precaution, stop using cannabis for at least six months before trying to conceive."