300mg CBD Shows Promise for Sleep in Worriers — But Doesn't Beat Placebo | Research

The takeaway

In high-worry individuals, 300 mg CBD daily for two weeks improved sleep significantly more than 50 mg CBD, but did not significantly outperform placebo, leaving CBD's sleep benefits unconfirmed.

People considering CBD for sleep, clinicians advising on CBD use, sleep researchers, and anyone interested in evidence-based assessment of CBD products.

What the researchers found

300 mg CBD decreased sleep disturbances significantly more than 50 mg CBD (B=-0.39, t=-2.59, p<0.05, d=0.08) but not significantly more than placebo (B=-0.32, t=-2.09, p=0.10, d=0.07), with no effects on sedation or cognitive impairment.

Why it matters

Despite massive consumer interest in CBD for sleep, this rigorous trial found that CBD beat a lower dose but couldn't clearly beat placebo — highlighting the gap between marketing claims and evidence.

The numbers in context

n=63; mean age 29.27; 300 mg vs 50 mg CBD significant (p<0.05, d=0.08); 300 mg vs placebo not significant (p=0.10, d=0.07); 2-week treatment; no sedation effects; no cognitive impairment

How the study worked

Randomized, double-blind, placebo-controlled trial with 63 individuals reporting elevated trait worry, assigned to 300 mg CBD, 50 mg CBD, or placebo daily for 2 weeks, measuring sleep disturbances, sleep quality, sedation, and cognitive function.

What this study cannot tell us

Small sample (n=63); very small effect sizes (d=0.07-0.08); only 2-week duration; self-report sleep measures; trait worry sample may not generalize; only two CBD doses tested; borderline p-value vs. placebo suggests possible underpowering.

How to read the evidence

Well-designed RCT but underpowered (n=63) with very small effect sizes, yielding inconclusive results for the primary comparison against placebo.

When this study was published

Published 2026; represents latest clinical evidence on CBD and sleep.

The bigger picture

The inability of 300 mg CBD to significantly outperform placebo for sleep underscores how little rigorous evidence supports the massive CBD-for-sleep consumer market.

Questions still open

Would a larger sample reveal a significant placebo comparison? Would higher doses or longer treatment show clearer effects? Is the sleep benefit mediated by anxiety reduction rather than direct sleep effects?

Common questions

Does CBD help you sleep?

This trial found that 300 mg daily CBD improved sleep more than 50 mg CBD in people with high worry, but the improvement was not significantly better than placebo — meaning the evidence remains inconclusive.

What dose of CBD is needed for sleep?

300 mg outperformed 50 mg in this study, but neither dose clearly beat placebo for sleep outcomes, suggesting that if CBD has sleep benefits, they may require higher doses or longer treatment periods to demonstrate.

Read the original research

The effects of cannabidiol on sleep disturbances within a sample of high trait worriers: A double-blind, randomized placebo controlled trial.

Experimental and clinical psychopharmacology

View on PubMed ↗Publisher’s paper ↗

Citation

Gournay, L Riley; Ferretti, Morgan L; Dickens, Harrison B; Floyd, Veronica; Fernandez, Daniella A; Rathbun, Ezri; Nguyen, Anna-Marie; Leen-Feldner, Ellen W. (2026). The effects of cannabidiol on sleep disturbances within a sample of high trait worriers: A double-blind, randomized placebo controlled trial.. Experimental and clinical psychopharmacology. https://doi.org/10.1037/pha0000832