Smoking marijuana may cause gynecomastia, also known as man boobs, according to plastic surgeon Dr. Anthony Youn.
Gynecomastia can occur when a man has more estrogen in his body than testosterone, which can result in the development of more breast tissue than what is typical in most men, Youn explains
in an editorial he wrote for CNN.
The active ingredient cannabis has been shown to decrease the testosterone levels in animals, creating an imbalance in the ratio of testosterone to estrogen. This also causes testicles to shrink and abnormalities to develop as well as affects how sperm functions.
This may not necessarily be the case in humans. However, some studies have shown that chronic marijuana users do have lower testosterone levels than nonusers.
A study done in 1972 did show a link between pot smoking and gynecomastia, while a 1977 study did not. However, the Michigan plastic surgeon notes that the 1977 study suffered from a small sample size and may not be very accurate.
"The legalization of marijuana is some state[s] could make it easier for researchers to determine the exact effects of cannabis use on hormone levels, gynecomastia and other bodily functions," Youn explains. "If a true link between smoking pot and gynecomastia does exist, then we should expect to see a spike in gynecomastia treatments in those states which have legalized marijuana."
According to the American Society for Aesthetic Plastic Surgery, there was a 30 percent increase in the number of men undergoing plastic surgery to correct gynecomastia from 2011 to 2012.
Youn concludes smoking pot "probably" can give someone man boobs even though more studies are still needed to prove the connection.
He added that it has become routine for himself and the majority of other plastic surgeons he has talked to to ask gynecomastia patients if they smoke pot, and if so, "it's probably best to put out that joint."
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