Until recently, CBD was an underappreciated compound in cannabis. Growers actually tried to breed it out of plants, seeking strains with higher THC levels, according to Martin Lee, a cannabis historian. It wasn’t until 2009, he says, that growers came across plants containing large amounts of CBD.
Some research suggests that CBD may affect the “endocannabinoid system,” a series of receptors found throughout the body that seem to interact with various compounds in cannabis, including CBD, and some of which are related to feelings of anxiety and pain, or that help regulate the body’s sleep-wake cycles.
CBD’s most far-reaching health effect may be its anti-inflammatory properties. And not just in a knee or hip joint, but throughout the body, including the central nervous system and the brain, says Joseph Maroon, M.D., a clinical professor of neurological surgery at the University of Pittsburgh Medical Center, who has investigated the link. In a 2018 review, he and colleagues said such effects could possibly reduce anxiety, depression, seizures, and post-traumatic stress disorder (PTSD), and even benefit people who have had a concussion.
The best studies of CBD so far have been in the area of seizures, and the results were strong enough that last year the Food and Drug Administration approved a prescription version of CBD, called Epidiolex.
CR’s survey also provides some support for CBD’s possible health benefits. Almost three-quarters of people who took CBD said it was at least moderately effective for the main reason they took it, with 48 percent of them saying it was very or extremely effective.
And CBD seemed to work well for some of the most common problems, including easing stress and joint pain, and improving sleep. Our survey also suggests that side effects are uncommon; almost three-quarters said they experienced no side effects.