A Randomized Clinical Trial Exploring Two Doses of Cannabidiol Daily for Eight Weeks on Health and Stress

This study’s purpose was to explore whether a 60 or 30 mg dose of cannabidiol (CBD) consumed in a beverage further supplemented with L-theanine, vitamin E, and vitamin C would alter various measures on subjective measures of stress, health and fitness related outcomes, and objective measures of stress. This double-blind, placebo-controlled clinical trial recruited healthy, college-aged subjects for randomization into one of four treatment groups where they consumed daily a single 12 ounce beverage for eight weeks containing 1) 60 mg CBD (CBD60) plus L-theanine; 2) 30 mg CBD (CBD30) plus L-theanine; 3) no CBD (CBD0), L-theanine alone, and 4) a vehicle control (PLAC) containing no additives. Surveys evaluated stress and sleep while a Fitbit wrist monitor collected physical activity and sleep data. Anaerobic performance was evaluated with a Wingate test. Fasted blood concentrations of cortisol and C-reactive protein (CRP) were analyzed with an ELISA. Furthermore, utilizing the perceived stress scale, participants were separated into low-stress and high-stress groups for further analysis, to identify if the higher doses of CBD will elicit larger improvements in the measures gathered. The pre-intervention time point differences were determined by a one-way ANOVA, and treatment effects were identified with 4×2 ANOVA 4×2×2 ANOVA. A total of 102 healthy participants were randomly assigned to CBD60 (n = 25), CBD30 (n = 28), CBD0 (n = 24), or PLAC (n = 25). There were no differences among the groups at the pre-intervention time point, and the average age of the participants was 24.4 ± 7.0 years, with an average BMI 23.9 ± 3.6 kg/m2. Following the eight-week intervention period, there were no significant CBD treatment effects with respect to perceived stress, sleep, body composition, voluntary physical activity, and anaerobic performance measures. Additionally, circulating concentrations of serum cortisol and CRP were similar between the treatment groups. Our findings suggested that when 60 or 30 mg of CBD was added to a beverage containing L-theanine, vitamin E, and vitamin C, and consumed daily for 8 weeks, it was overall well tolerated in this younger, generally healthy population. However, CBD had no significant impact, either positive or negative, on subjective measures of stress, health and fitness-related outcomes, and objective measures of stress.