CBS Los Angeles — The ability to use marijuana legally in Colorado has reportedly resulted in a positive side-effect: a decrease in the number of fatal opioid overdoses in the state.

According to a new study by the American Journal of Public Health, the number of overdose deaths have fallen by more than six percent since the state legalized recreational pot in 2014.

“Colorado’s legalization of recreational cannabis sales and use resulted in a 0.7 deaths per month reduction in opioid-related deaths,” researchers wrote.

While fatal overdoses have dropped in Colorado, local officials are skeptical of the connection to legal marijuana. “It just hasn’t been in place long enough,” Dr. Larry Wolk said, via The Denver Post. “Anything that does get published at this point should be considered preliminary data,” the director of the Colorado Department of Public Health added.

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