In the meantime, some physicians are forging ahead — and cashing in. Joe Cohen is a doctor at Holos Health, a medical marijuana clinic in Boulder. I asked him what CBD is good for, and he read me a long list of conditions: pain, inflammation, nausea, vomiting, intestinal cramping, anxiety, psychosis, muscle spasms, hyperactive immune systems, nervous system degeneration, elevated blood sugar and more. He also claimed that CBD has anti-cancer properties and can regenerate brain cells and reduce the brain’s levels of amyloid beta — a kind of protein that’s been linked to Alzheimer’s disease. I asked for references, noting that most of these weren’t listed in the Academies report or a similar review published in the Journal of the American Medical Association. “I think you just have to Google search it,” he said. It’s true that a preliminary study found hints that cannabinoids might reduce beta amyloid proteins in human brain cells, but the study was done in cells grown in a lab, not in people. As for cancer, the FDA sent warning letters last year to four companies that were selling products that claimed to “prevent, diagnose, treat or cure” cancer.
Last year, the National Academies of Sciences, Engineering and Medicine released a nearly 500-page report on the health effects of cannabis and cannabinoids. A committee of 16 experts from a variety of scientific and medical fields analyzed the available evidence — more than 10,000 scientific abstracts in all. Because so few studies examine the effects of CBD on its own, the panel did not issue any findings about CBD specifically, but it did reach some conclusions about cannabis and cannabinoids more generally. The researchers determined that there is “conclusive or substantial evidence” supporting the use of cannabis or cannabinoids for chronic pain in adults, multiple sclerosis-related spasticity (a kind of stiffness and muscle spasms), and chemotherapy-induced nausea and vomiting. The committee also found “moderate” evidence that cannabis or cannabinoids can reduce sleep disturbances in people with obstructive sleep apnea, fibromyalgia, chronic pain and multiple sclerosis, as well as “limited” evidence that these substances can improve symptoms of Tourette’s syndrome, increase appetite and stem weight loss in people with HIV/AIDs, and improve symptoms of PTSD and anxiety.
Those warning letters aside, there’s not a lot of federal oversight right now over the claims being made or the products that are being sold. Cohen warned against buying CBD products online, because “there’s a lot of scams out there.” Yet his clinic sells CBD, and he admits, “I say ‘Don’t buy online,’ but ours is worth doing, because we know what we’re doing. We ship all over.”
As marijuana is legalized in more and more states, the wellness world has whipped itself into a frenzy over a non-intoxicating cannabis derivative called cannabidiol. CBD products can be found on the internet and in health-food stores, wellness catalogs and even bookstores. (A bookstore in downtown Boulder, Colorado, displays a case of CBD products between the cash register and the stacks of new releases.) Celebrities like Gwyneth Paltrow, disgraced cyclist 1 Floyd Landis and former Denver Broncos quarterback Jake Plummer are all touting CBD products, and according to Bon Appétit, CBD-infused lattes have become “the wellness world’s new favorite drink.”
Cannabinoids are a class of compounds that interact with receptors throughout your body. CBD is just one of dozens of cannabinoids found in cannabis, including tetrahydrocannabinol (THC), which is the one responsible for marijuana’s famous high. Medical cannabis is technically any cannabis product used for medicinal purposes, and these can contain THC or CBD or both, said Nick Jikomes, a neuroscientist at Leafly, a website that provides information about legal cannabis. “A common mistake people make is to think that CBD is ‘the medical cannabinoid’ and THC is ‘the recreational cannabinoid.’” That’s inaccurate, he said, because THC is a potent anti-inflammatory and can be helpful for pain.
Although there’s enticing evidence that good ol’ cannabis can ease chronic pain and possibly treat some medical conditions, whether CBD alone can deliver the same benefits remains an open question. What is clear, at this point, is that the marketing has gotten way ahead of the science.
Most of these products promised to relieve pain or otherwise enhance well-being, and none of it was cheap. (Prices started at about $30.) But I wanted to know: Does any of this stuff really work? After a deep dive into the scientific research, I learned that the answer was a big fat maybe.
So what do we know about these popular uses for CBD?
Are you a rat or a mouse? If so, chances are good that CBD administered in moderate doses—10 mg/kg is too low; 100 mg/kg is too high—could have an anti-anxiety effect, particularly if you’re feeling anxious because you’ve been placed in a maze or are panicking because a snake has been introduced to your environment.
Is there proof that CBD works for all this?
(Cannabidiol made a splash in the news as a potential treatment for seizures in 2013, when CNN’s Sanjay Gupta featured the story of a Colorado couple, Matt and Paige Figi, who were using CBD oil to treat their daughter Charlotte’s seizures. The Stanley Brothers—the family business that provided that oil—said they heard from thousands of families following the story, and so was born Charlotte’s Web, one of the world’s biggest CBD companies.)
(In this bonkers and somewhat upsetting 2012 study, scientists observed the behavior of mice, some of which were pre-treated with CBD, after a wild boa constrictor was introduced to an “arena” with them. Spoiler alert: “In no case did a snake eat an experimental mouse.” But the CBD-treated mice did exhibit fewer “panic-like” responses, such as freezing, urinating, or attempting an “explosive escape,” when faced with the snake. Researchers concluded the CBD-treated mice were experiencing less fear than those who got the placebo, despite this truly terrifying scenario. So there’s that.)
In one cringe-inducing study, scientists evaluated rats’ sensitivity to pain by exposing their sciatic nerves with an incision, constricting those nerves with tiny threads, or injecting their paws with bacteria to induce inflammation. Then, they fed them CBD or a placebo every day for a week, and measured how quickly the critters withdrew their legs when exposed to heat or pressure, compared to how they reacted before their respective surgeries or injections.
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But many people still don’t really know what CBD is. Is it marijuana? Is it legal? Does it actually work? Is it safe?
By now, you’ve probably run into a product containing cannabidiol, also known as CBD. It’s in everything from drinks and pet products to lotions and chewable gummies. Even major drugstore chains have announced they will start carrying CBD products in certain states.
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