All analyses were conducted in SPSS version 24 (IBM Corporation, Armonk, NY). Valid percentages are reported rather than absolute values for descriptive statistics to account for missing data. We only report data on those reporting using CBD themselves equivalent to 90% of the respondents (e.g., not for veterinary use, not those who had not tried it, and those reporting on behalf of other users). An analysis of non-responders can be found in supplementary materials. We conducted logistic regression models to investigate associations between sex (males [reference category] and females), age (recoded to < 34 years old [reference category], between 35 and 54 years old, and 55+) and location (UK [reference category], other). For CBD use patterns, we used separate models to compare those who did and did not report their primary use of CBD for self-perceived anxiety, stress, and sleep whilst controlling for sex, age, and location. We dummy-coded “time of day” as each category versus all others. We report adjusted odds ratios with 95% confidence intervals and p values with a defined cut-off of 0.05.
The sample (N = 387) consisted of 61.2% females, mostly between 25 and 54 years old (72.2%) and primarily based in the UK (77.4%). The top 4 reasons for using CBD were self-perceived anxiety (42.6%), sleep problems (42.5%), stress (37%), and general health and wellbeing (37%). Fifty-four per cent reported using less than 50 mg CBD daily, and 72.6% used CBD sublingually. Adjusted logistic models show females had lower odds than males of using CBD for general health and wellbeing [OR 0.45, 95% CI 0.30–0.72] and post-workout muscle-soreness [OR 0.46, 95%CI 0.24–0.91] but had higher odds of using CBD for self-perceived anxiety [OR 1.60, 95% CI 0.02–2.49] and insomnia [OR 1.87, 95% CI 1.13–3.11]. Older individuals had lower odds of using CBD for general health and wellbeing, stress, post-workout sore muscles, anxiety, skin conditions, focusing, and sleep but had higher odds of using CBD for pain. Respondents reported that CBD use was effective for stress, sleep problems, and anxiety in those who used the drug for those conditions.
The majority of users take CBD sublingually for 3–6 months (see Table 2). Those 35–54 years old (aOR 1.67 [95% CI 1.02–2.72], p = 0.04) and those 55+ (aOR 2.01, [95% CI 1.11–3.64], p = 0.02) had greater odds of using CBD daily in comparison to less than daily. There were no associations with self-perceived anxiety, stress, or sleep improvement. Females had lower odds of using CBD for greater than 1 year versus less than 1 year (aOR 0.54, [95% CI 0.38–0.88], p = 0.013) suggesting females had used CBD for less time. No associations emerged for self-perceived anxiety, stress, or sleep. There were no sex or age associations for the frequency of use, duration of use, or number of times per day. Females had a greater odds of responding that they take CBD when they need it versus males (aOR 1.79, [95% CI 1.036–3.095], p = 0.037). However, no other associations with age and sex on time of day emerged.
As we initially designed the study to address sleep, we asked detailed questions regarding this. Improving sleep (125/387; 32.3%) and self-perceived insomnia (95/387; 24.5%) were the fourth and fifth-ranked endorsed reasons for using CBD, overall 42.5% endorsed sleep as a reason for use. Respondents said that CBD helped them sleep (see Fig. 2). As we restricted this analysis to respondents who selected using CBD for sleep improvement, there was considerable overlap between using CBD for sleep improvement and self-perceived insomnia. Regarding questions about the time it takes to fall asleep, 48.2%(73/124;) said CBD led them to fall asleep faster, followed by 29/124 (23.4%) who said it did not make a difference and still have a hard time falling asleep, followed by 22/124 (17.7%) who said it did not make a difference because they did not have a problem falling asleep beforehand. Age, sex, and location were not associated with the speed of falling asleep.
One hundred sixty-five of 387 (42.6%) endorsed using CBD for self-perceived anxiety. In response to the question “how does CBD affect your anxiety levels”, participants responded that they felt less anxious (141/163 (86.5%)), followed by “no difference (I still suffer from the same degree of anxiety)” (21/163; 12.8%), and one person (0.6%) noted greater anxiety. Moreover, participants were asked how often they thought about problems when they were supposed to be relaxing, compared with before they started taking CBD. We found that just 96/163 (58.9%) of respondents thought about their problems less than before, followed by “it hasn’t changed (I still think a lot about problems” (55/163; 33.7%), followed by “it hasn’t changed (I did not think about problems a lot before)” (11/163; 6.7%), followed by (1/163; 0.6%) of respondents reporting thinking about problems more than before.
CBD has been touted for a wide variety of health issues, but the strongest scientific evidence is for its effectiveness in treating some of the cruelest childhood epilepsy syndromes, such as Dravet syndrome and Lennox-Gastaut syndrome (LGS), which typically don’t respond to antiseizure medications. In numerous studies, CBD was able to reduce the number of seizures, and, in some cases, it was able to stop them altogether. Videos of the effects of CBD on these children and their seizures are readily available on the Internet for viewing, and they are quite striking. Recently the FDA approved the first ever cannabis-derived medicine for these conditions, Epidiolex, which contains CBD.
Side effects of CBD include nausea, fatigue and irritability. CBD can increase the level in your blood of the blood thinner coumadin, and it can raise levels of certain other medications in your blood by the exact same mechanism that grapefruit juice does. A significant safety concern with CBD is that it is primarily marketed and sold as a supplement, not a medication. Currently, the FDA does not regulate the safety and purity of dietary supplements. So, you cannot know for sure that the product you buy has active ingredients at the dose listed on the label. In addition, the product may contain other (unknown) elements. We also don’t know the most effective therapeutic dose of CBD for any particular medical condition.
The evidence for cannabidiol health benefits
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CBD is readily obtainable in most parts of the United States, though its exact legal status is in flux. All 50 states have laws legalizing CBD with varying degrees of restriction, and while the federal government still considers CBD in the same class as marijuana, it doesn’t habitually enforce against it. In December 2015, the FDA eased the regulatory requirements to allow researchers to conduct CBD trials. Currently, many people obtain CBD online without a medical cannabis license. The government’s position on CBD is confusing, and depends in part on whether the CBD comes from hemp or marijuana. The legality of CBD is expected to change, as there is currently bipartisan consensus in Congress to make the hemp crop legal which would, for all intents and purposes, make CBD difficult to prohibit.
CBD may offer an option for treating different types of chronic pain. A study from the European Journal of Pain showed, using an animal model, CBD applied on the skin could help lower pain and inflammation due to arthritis. Another study demonstrated the mechanism by which CBD inhibits inflammatory and neuropathic pain, two of the most difficult types of chronic pain to treat. More study in humans is needed in this area to substantiate the claims of CBD proponents about pain control.
The CBD industry is flourishing, conservatively projected to hit $16 billion in the United States by 2025. Already, the plant extract is being added to cheeseburgers, toothpicks and breath sprays. More than 60 percent of CBD users have taken it for anxiety, according to a survey of 5,000 people, conducted by the Brightfield Group, a cannabis market research firm. Chronic pain, insomnia and depression follow behind. Kim Kardashian West, for example, turned to the product when “freaking out” over the birth of her fourth baby. The professional golfer Bubba Watson drifts off to sleep with it. And Martha Stewart’s French bulldog partakes, too.
This year, 1,090 people have contacted poison control centers about CBD, according to the American Association of Poison Control Centers. Over a third are estimated to have received medical attention, and 46 were admitted into a critical care unit, possibly because of exposure to other products, or drug interactions. In addition, concern over 318 animals poured into the American Society for the Prevention of Cruelty to Animals’ Animal Poison Control Center.
What is CBD?
A recent chart review of 72 psychiatric patients treated with CBD found that anxiety improved, but not sleep. “Over all, we did not find that it panned out as a useful treatment for sleep,” said Dr. Scott Shannon, assistant clinical professor of psychiatry at the University of Colorado, Denver and the lead author of the review in The Permanente Journal.
Earlier research found fewer than a third of 84 products studied contained the amount of CBD on their labels. Some users of CBD have also failed drug tests when the product contained more THC than indicated.
For students with generalized social anxiety, a four-minute talk, with minimal time to prepare, can be debilitating. Yet a small experiment in the journal Neuropsychopharmacology found that CBD seemed to reduce nervousness and cognitive impairment in patients with social anxiety in a simulated public speaking task.