Abstract
Background
Saffron, derived from the stigmas of the Crocus sativus flower, has been shown in previous trials to have antidepressant effects in clinically diagnosed adults. However, the recruitment of small sample sizes, short treatment periods, and variability in the quality of studies have negatively impacted the strength of conclusions.
Objectives
The purpose of this 2-arm, 12-wk, parallel-group, randomized, double-blind, placebo-controlled trial was to examine the effects of supplementation with a saffron extract (Affron) on mood and sleep in adults experiencing subclinical depressive symptoms.
Methods
Two hundred and two adults aged 18–70 with depressive symptoms were supplemented with 28 mg saffron daily or a placebo. Outcome measures included the Depression, Anxiety, and Stress Scale – 21, Sleep Disturbance and Sleep-Related Impairment Scale, World Health Organization–Five Well-Being Scale, and daily depression, stress, and anxiety ratings.
Results
On the primary outcome measure, compared to the placebo, saffron was associated with greater improvements in the Depression, Anxiety, and Stress scale – 21 depression score (β: –2.92 points; 95% confidence interval: –5.13, –0.71 points; Cohen’s d = 0.39), with 72.3% of participants in the saffron group achieving a clinically significant change (a reduction of ≥ 7 points) compared to 54.3% of participants in the placebo group (P = 0.010). However, in the other secondary outcomes, there was no evidence of between-group differences. In exploratory analyses across various strata and assumptions, improvements in sleep disturbances (β: –2.72 points; 95% confidence interval: –4.99, –0.46 points; Cohen’s d = 0.44) were identified in a subset of participants with a greater severity of sleep disturbance. There were no serious adverse reactions reported.
Conclusions
This study, the largest conducted to date on saffron, provides evidence supporting the beneficial effects of 3 mo of saffron supplementation on depressive symptoms in adults. Large placebo responses were evident in this study, which require consideration in future trials.
This trial was registered at Australian and New Zealand clinical trials registry as ACTRN12623001358639.