Effectiveness of an <i>Arthrospira platensis</i> (Spirulina) Softgel Supplementation on Sleep Quality, Mental Health Status, and Body Mass Index in Mild to Moderately Severe Depression Adults: A Double‐Blinded, Randomized, Placebo‐Controlled Trial

<i>Arthrospira platensis</i> (Spirulina) has been recognized for its diverse benefits to human health. Currently, stress and sleep disorders are prevalent and increasing annually worldwide. This study aimed to conduct a randomized controlled trial to assess the effects of Spirulina on sleep quality, mental health status, and body mass index (BMI) measurements in adults with mild to moderately severe depression. Sixty-six participants with mild to moderately severe depression were randomly assigned to receive either 2 g/day of Spirulina (two 1000 mg capsules) (<i>n</i> = 33) or a placebo (<i>n</i> = 33) for 8 weeks. Assessments conducted at baseline, week 4, and the end of the intervention included General Interview Questionnaires (GIQ), BMI, pulse and blood pressure measurements, the Depression Anxiety Stress Scales (DASS-21), the Pittsburgh Sleep Quality Index (PSQI), and the Sleep Hygiene Index (SHI). Sixty-three participants completed the trial. Adherence to supplementation was high, with two participants in the Spirulina group reporting missed doses for one day and 3 days, respectively. Out of 66 participants, three from the control group dropped out by the end of the study. Analysis using repeated measures ANOVA revealed a significant difference in PSQI scores in the experimental group from baseline to 8 weeks, with the mean score decreasing from 7.03 ± 3.52 to 4.97 ± 1.98. The control group's mean score decreased from baseline to week 4, followed by a slight increase by week 8. Comparing the experimental and control groups at week 8, the mean PSQI scores differed significantly, with 4.97 ± 1.98 and 6.73 ± 2.69 (95% CI [-2.945, -0.582], <i>p</i> = 0.004). Significant differences were found in sleep quality and sleep latency between the groups, with scores of 0.82 ± 0.58 and 1.33 ± 0.61 (95% CI [-0.815, -0.215], <i>p</i> = 0.001) and 0.79 ± 0.70 and 1.33 ± 0.71 (95% CI [-0.900, -0.191], <i>p</i> = 0.003), respectively. Both groups showed statistically significant decreases in DASS-21 scores. The experimental group exhibited gradual reductions across all assessments (19.27 ± 13.09, 14.24 ± 10.13, 11.58 ± 8.19) at <i>p</i> < 0.05. Conversely, the control group saw an increase in mean scores by week 8 (15.43 ± 9.18, 12.57 ± 9.83, 12.63 ± 10.50). BMI indices and blood pressure exhibited no statistically significant changes (<i>p</i> > 0.05). Sleep quality, sleep latency, and mental health improved after <i>Arthrospira platensis</i> daily softgel supplementation. Further clinical studies, potentially conducted over extended periods, could provide additional support for the trends observed in this study.