Marijuana
![A farmer planting his marijuana crop.](https://cdn.mos.cms.futurecdn.net/vovUtUGKvs7cfLysUCbhTU-320-80.jpg)
Marijuana is an age-old drug made from parts of the Cannabis plant. It contains the mind-altering chemical tetrahydrocannabinol, or THC. Several countries, and a number of U.S. states, have legalized the drug for medical or recreational purposes. Here's the latest news on marijuana, from how it affects the brain and body, to its potential medical benefits or harms, to possible impacts of legalization.
Latest about Marijuana
![close up photo of a person handing a joint to a second person to smoke](https://cdn.mos.cms.futurecdn.net/i72UTKnbzCftCftStfuARC-320-80.jpg)
Cannabis use linked to head and neck cancer risk
By Nicoletta Lanese published
A new study that looked at 20 years of medical data from millions of people found a link between cannabis use and specific cancers.
![Close-up image of a joint being passed from one person's hands (on the right side of the image) to another (on the left side of the image). The hand on the left has a gold ringer on two fingers.](https://cdn.mos.cms.futurecdn.net/F2cNZ9U3aaf2ndW2MDFhcT-320-80.jpg)
Could cannabis treat cancer someday? Here's what the science says so far
By Emily Cooke published
For decades, cannabis has been studied for its potential antitumor properties, but whether it can actually treat cancer is still unknown.
![Two women laugh and smile as they run on treadmills.](https://cdn.mos.cms.futurecdn.net/WrCkzP4Rj86sB99Sq6fHB8-320-80.jpg)
Runners enjoyed their workouts more after using cannabis, but physically floundered
By Emily Cooke published
Smoking cannabis before a workout may make the experience more enjoyable, but it may feel harder, a small study suggests.
![microscopic image of the nematode c elegans. specific cells are stained bright green, and others are bright pink](https://cdn.mos.cms.futurecdn.net/w4sPpkpGBrhYT7xnX7mzxJ-320-80.jpg)
Worms and humans both get 'the munchies,' despite 500 million years of evolutionary separation
By Soumya Sagar published
Researchers found that roundworms gobble down high-calorie foods when exposed to a compound that acts on the same brain receptor as THC.
![A farmer puts his marijuana plant into soil](https://cdn.mos.cms.futurecdn.net/b3AU4veJYLuXdjYUGeooCn-320-80.jpg)
'High Holiday' 420 has hazy origins
By Tia Ghose last updated
Though there are many urban legends out there, the origins of 4/20 as an international holiday to smoke marijuana are hazy.
![close up of white, orange and pink gummies bears scattered on a table next to clumps of dried cannabis](https://cdn.mos.cms.futurecdn.net/d2Hgi4uBtrJf9xyqV4SaA-320-80.jpg)
Cannabis poisonings in young kids skyrocketed following legalization of edibles
By Nicoletta Lanese published
The rate of children being hospitalized for cannabis poisoning increased in Canadian provinces that legalized edibles.
![Many people use cannabis to manage pain.](https://cdn.mos.cms.futurecdn.net/VpNWQhLmtiQEb89oWcemtg-320-80.jpeg)
Cannabis is no better than a placebo for treating pain, 20 studies show
By Filip Gedin published
Cannabis is one of the most widely used drugs in the world. While there are only a few countries where cannabis is legal for recreational use, many more countries have legalized the use of cannabis for medical reasons.
![A baby skunk about to spray.](https://cdn.mos.cms.futurecdn.net/X6p7H9CcXNcLedN73i33sN-320-80.jpg)
Why does cannabis smell skunky?
By John Arnst published
Cannabis has long been called "skunky." Turns out, stinky sulfurous compounds are to blame.
Sign up for the Live Science daily newsletter now
Get the world’s most fascinating discoveries delivered straight to your inbox.