A new study published this week the journal Human Reproduction may go a long way in combating the lazy stoner stereotype.
When Dr. Jorge Chavarro and his team of researchers at Harvard began investigating marijuana's effects on men, they didn't expect to find anything new. After all, previous studies on how weed affects reproduction has shown detrimental effects to "testicular function". However, Chavarro's team found the opposite. In fact, the study found that men who had ever smoked marijuana in their life were found to have significantly higher sperm concentrations and higher levels of testosterone as compared to men who had never smoked weed.
"These findings are not consistent with a deleterious role of marijuana smoking on testicular function as initially hypothesized," Chavarro and his colleagues said in the journal Human Reproduction.
Overall, men who reported smoking at least two joints per day were found to be producing higher-quality sperm according to the study. Previous studies on the subject of testosterone production and sperm counts have linked stoners with lower sperm production.
Chavarro's team can't explain the findings, but they did offer several hypotheses on what might be happening. For one, men with higher circulating testosterone concentrations are more likely to engage in 'risk-taking behaviors" which includes smoking pot. The study examined 600 men who were at fertility clinics and more than 1,000 sperm samples over 17 years.
It's also possible that the weed stimulates sperm production in men, but reverses the more the individual smokes. Much like having a glass of wine is recommended for many to lower heart disease, while drinking an entire bottle isn't.
But, as more states legalized recreational marijuana, Chavarro and his team cautioned that the results from his study should be interpreted with caution and that more research is needed to determine how weed works on the human body.
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