National Geographic : 2015 Jun
40 national geographic • June 2015 to discuss the explosion of interest in the sci- ence of marijuana. “Mea culpa!” he replies with a smile. Israel has one of the world’s most advanced medical marijuana programs. Mechoulam played an active role in setting it up, and he’s proud of the results. More than 20,000 patients have a license to use cannabis to treat such conditions as glaucoma, Crohn’s disease, inflammation, appetite loss, Tourette’s syndrome, and asthma. Despite that, he’s not particularly in favor of legalizing cannabis for recreational use. He doesn’t think anyone should go to jail for possessing it, but he insists that marijuana is “not an innocuous substance”—especially for young people. He cites studies showing that the prolonged use of high-THC strains of mari- juana can change the way the developing brain grows. He notes that in some people cannabis can provoke serious and debilitating anxiety attacks. And he points to studies that suggest cannabis may trigger the onset of schizophre- nia among those who have a genetic predispo- sition to the disease. If he had his way, what Mechoulam regards as the often irresponsible silliness of recreation- al pot culture would give way to an earnest and enthusiastic embrace of cannabis—but only as a medical substance to be strictly regulated and re- lentlessly researched. “Right now,” he complains, “people don’t know what they’re getting. For it to work in the medical world, it has to be quantita- tive. If you can’t count it, it’s not science.” In 1992 Mechoulam’s quest for quantifica- tion led him from the plant itself to the inner recesses of the human brain. That year he and several colleagues made an extraordinary dis- covery. They isolated the chemical made by the human body that binds to the same receptor in the brain that THC does. Mechoulam named it anandamide—from the Sanskrit for “supreme joy.” (When asked why he didn’t give it a He- brew name, he replies, “Because in Hebrew there are not so many words for happiness. Jews don’t like being happy.”) Since then several other so-called endocan- nabinoids and their receptors have been dis- covered. Scientists have come to recognize that endocannabinoids interact with a specific neu- rological network—much the way that endor- phins, serotonin, and dopamine do. Exercise, Mechoulam notes, has been shown to elevate endocannabinoid levels in the brain, and “this probably accounts for what jogging enthusi- asts call runner’s high.” These compounds, he explains, apparently play an important role in such basic functions as memory, balance, move- ment, immune health, and neuroprotection. Typically, pharmaceutical companies mak- ing cannabis-based medicines have sought to isolate individual compounds from the plant. But Mechoulam strongly suspects that in some cases those chemicals would work much better in concert with other compounds found in mar- ijuana. He calls this the entourage effect, and it’s just one of the many cannabis mysteries that he says require further study. “We have just scratched the surface,” he says, “and I greatly regret that I don’t have another lifetime to devote to this field, for we may well discover that cannabinoids are involved in some way in all human diseases.” THE BOTANIST Into the Light The 44,000-square-foot building hulks across from a police station in an industrial part of Denver, along a gritty stretch of converted ware- houses that’s come to be known as the Green Mile. There’s nothing to indicate the nature of the enterprise. The door buzzes open, and I’m met by the chief horticulturist of Mindful, one of the largest cannabis companies in the world. A druidlike 38-year-old with keen blue eyes, Phillip Hague wears fatigues, hiking boots, and the incredulous grin of someone who—through a confluence of events he never imagined Hampton Sides, author of In the Kingdom of Ice and other histories, wrote about Russia’s Wrangel Island in May 2013. Lynn Johnson has photographed 23 stories for the magazine; her last was “Healing Soldiers” in February.