Marijuana's official designation in the US as a Schedule 1 drug— something with "no currently accepted medical use"— means it has been pretty tough to study.
Despite that, a growing body of research and numerous anecdotal reports link cannabis with several health benefits, including pain relief and the potential to help with certain forms of epilepsy. In addition, researchers say there are many other ways marijuana might affect health that they want to better understand — including a mysterious syndrome that appears to make marijuana users violently ill.
Along with several other recent studies, a massive report released last year by the National Academies of Sciences, Engineering, and Medicine helps sum up exactly what we know— and what we don't — about the science of weed. Here's what you should know about how marijuana affects the brain and body.
Marijuana use is linked to a rare syndrome that causes nausea and vomiting.
Most recently, a March 2019 study looked at over 2,500 cannabis-related ER visits in Colorado.They found that stomach issues like nausea and vomiting were the main driver of the trips, even before psychiatric problems like intoxication and paranoia.
In 2004, Australian doctors began looking into these stomach symptoms based on the experiences of a local woman who used to be able to smoke marijuana with no issue, and then seemingly out of nowhere began having adverse reactions that paralleled those in the 2019 study.
They gave her condition a name: cannabinoid hyperemesis syndrome, or CHS. The rare illness is still fairly new and understudied, but researchers believe it might affect a large population.
"CHS is certainly not very rare," Andrew Monte, an associate professor of emergency medicine at UCHealth University of Colorado Hospital who led the March study, previously told Business Insider. "We see it absolutely every week in our ER."
Marijuana can make you feel good.
One of weed's active ingredients, tetrahydrocannabinol, or THC, interacts with the brain's reward system, the part primed to respond to things that make us feel good, like eating and sex.
When overexcited by drugs, the reward system creates feelings of euphoria. This is also why some studies have suggested that excessive marijuana use can be a problem for some people — the more often you trigger that euphoria, the less you may feel during other rewarding experiences.
In the short term, it can also make your heart race.
Within a few minutes of inhaling marijuana, your heart rate can increase by between 20 and 50 beats a minute. This can last anywhere from 20 minutes to three hours, according to the National Institute on Drug Abuse.
The NASEM report found insufficient evidence to support or refute the idea that cannabis might increase the overall risk of a heart attack. The same report, however, also found some limited evidence that smoking could be a trigger for a heart attack.
See the rest of the story at Business Insider