America in 2014 faces an epidemic of drug overdoses. But it's not heroin, crack cocaine, or methamphetamines that's killing us. It's opioid pain relievers.

But new research just published in the prestigious Journal of the American Medical Association (JAMA) suggests that recent moves to legalize the use of medical marijuana for pain management may help to reverse the tide of opioid drug overdoses. Could it be that pot is part of the solution to this problem?

A bit of background
Opioids produced by Big Pharma include such recognized brand-names as Vicodin (hydrocodone), OxyContin (oxycodone), and most famously, morphine. Defined by the federal government's National Institute on Drug Abuse (NIDA) as "medications that relieve pain" by reducing "the intensity of pain signals reaching the brain," these and other opioids "can also produce drowsiness, mental confusion, nausea, constipation, and, depending upon the amount of drug taken, can depress respiration."

When combined with these drugs' propensity to produce "physical dependence" and "addiction" when used regularly over a period of weeks, and with the fact that opioid users sometimes "seek to intensify their experience by taking the drug in ways other than those prescribed," opioid users can potentially overdose on the drugs. The results can be seen in the following chart, compiled by New England Journal of Medicine from data "from the National Vital Statistics System of the Centers for Disease Control and Prevention, the Treatment Episode Data Set of the Substance Abuse and Mental Health Services Administration, and the Automation of Reports and Consolidated Orders System of the Drug Enforcement Administration."

NEJM data published in May 2014 simplify this graph in stark terms: "The rate of death from overdoses of prescription opioids in the United States more than quadrupled between 1999 and 2010 ... far exceeding the combined death toll from cocaine and heroin overdoses. In 2010 alone, prescription opioids were involved in 16,651 overdose deaths, whereas heroin was implicated in 3,036."

But here's the thing: One of the things that makes opioid pain relievers so dangerous to their users is the potential for addiction combining with the drugs' potentially serious health effects. By contrast, NIDA data suggests fewer than one in 10 pot smokers ever go on to become "dependent" on the drug -- much less addicted.

In states where the use of medical marijuana has been legalized for use in pain management, JAMA says that opioid overdoses resulting in death are now running 24.8% below average. According to JAMA's finding -- admittedly tentative at this early date -- the legalization of medical marijuana use may already have saved as many as 1,700 lives.

Big news, potentially
JAMA bases its findings on data for "annual opioid overdose mortality" cases in the three states (California, Oregon, and Washington) that have had legal medical marijuana laws in place prior to 1999, plus the 10 states (Alaska, Colorado, Hawaii, Maine, Michigan, Montana, Nevada, New Mexico, Rhode Island, and Vermont) that have enacted similar laws since 1999.

That's 13 states out of 50 -- a large enough collection of states to get researchers from the Johns Hopkins Bloomberg School of Public Health and the Philadelphia Veterans Affairs Medical Center wondering whether "medical cannabis laws are associated with significantly lower state-level opioid overdose mortality rates" for a reason.

Bloomberg School associate professor Colleen L. Barry, an author of the study, says the data "suggests the potential for many lives to be saved" by giving patients access to legal medical marijuana. As Barry points out -- and as NIDA confirms -- in direct contrast to the opioids, "medical marijuana is not susceptible to unintentional overdose." That fact alone suggests it could be a safer alternative to more dangerous -- and also legal -- opioids.

Foolish takeaway
For the time being, it must be emphasized that JAMA's report is speculative and not conclusive -- and a direct causal link between marijuana legalization and a decline in opioid painkiller mortality has not yet been established. But since the study was conducted, 10 more states plus the District of Columbia have been added to the list of jurisdictions now permitting medical marijuana use. The verdict might not yet be in -- but the data is already flowing in.

Rich Smith has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.