There’s a huge problem in America with overdoses related to pain killers like OxyContin or Vicodin. Deaths relating to pain-killer overdoses have tripled since 1991 and 46 people die every day in the US from these sorts of overdoses. However, in the 13 states that have legalized medical marijuana, 25% fewer people die of opioid overdoses each year.

A study published in JAMA Internal Medicine hypothesise that states which allow patients to treat pain with marijuana rather than opiates, or sometimes to supplement opiates, have fewer deaths by painkiller overdose. Marijuana is far less toxic than most opiate painkillers and that it’s pretty much impossible to die from an overdose of weed. Not everyone, however, agrees with this interpretation of the results.

Other researchers say that the reduction in overdose deaths cannot be linked to medical marijuana with certainty because marijuana isn’t widely prescribed to chronic pain patients. These scientists believe that there must be other factors present in the drop in deaths. Many states now have policies in place designed to cut down on over prescribing opiate painkillers. Another factor might be that many individuals who overdose on pain killers are already addicts, and states that take a progressive approach to treating addiction are more likely to take a progressive approach to marijuana.