What marijuana really does to your body and brain

Marijuana's official designation as a Schedule 1 drug - something with "no accepted medical use" - means it is pretty tough to study.

Yet both a growing body of research and numerous anecdotal reports link cannabis with several health benefits, ranging from pain relief to helping with certain forms of epilepsy. In addition, researchers say there are many other potential ways marijuana might affect health that they want to understand better.

A massive new report released in January 2017 by the National Academies of Sciences, Engineering, and Medicine (NASEM) helps sum up exactly what we know - and perhaps more importantly, what we don't - about the science of weed.