Mental health issues and sleep disorders have surged globally, especially after COVID-19, impacting productivity and healthcare costs.
Thank you for reading this post, don't forget to subscribe!In Thailand, depression and insomnia rates continue to rise, with over 19 million people affected by sleep disturbances. While medications like benzodiazepines offer short-term relief, they carry risks of dependency and side effects, driving demand for safer, natural solutions.
Spirulina, a blue-green algae high in tryptophan, is available as a dietary supplement (often in tablets or capsules) and provides amino acids, vitamins, and antioxidants that may support better sleep and stress management.
Early studies have suggested it could reduce stress and enhance sleep quality, but no clinical trials have tested its effects on adults with mild to moderate depression.
As such, researchers at Thailand’s Mahidol University, Suranaree University of Technology and Chiang Mai University conducted a new double-blind, placebo-controlled trial on the effects of spirulina on sleep quality and mental health.
Spirulina supports slumber
The study enrolled healthy adults aged 18 to 60 with mild to moderate depression and a BMI under 30, excluding pregnant or breastfeeding individuals, night shift workers, severe psychiatric cases, heavy smokers or drinkers, recent travellers, and those using sleep or weight-loss supplements.
The randomized, placebo-controlled trial used blinded group assignments and assessed mental health, sleep quality, and sleep hygiene at baseline, week 4, and week 8.
The supplement used in the trial delivered two grams per day of Arthrospira platensis (spirulina) over eight weeks. The researchers found that this relatively low dose was enough to yield measurable benefits in sleep quality. They also noted that participants maintained their normal diets and routines during the study, isolating the effect of the spirulina supplement.
By the end of eight weeks, participants taking spirulina had significantly better Pittsburgh Sleep Quality Index (PSQI) scores (4.97 on average, down from 7.03 at baseline) than the placebo group (6.73 at week 8). In particular, sleep quality and sleep latency (the time it takes to fall asleep) improved in the spirulina group versus placebo.
Those taking also experienced more restful sleep — this was especially notable because insomnia and poor sleep are common in people with depression.
Less stressed and depressed
In addition to sleep benefits, the participants’ mental health status improved with spirulina. Scores on the Depression Anxiety Stress Scales (DASS-21) — a standard questionnaire for mood and stress — dropped steadily in the spirulina group, from an average of about 19 (mild-moderate range) at the start to 12 by week 8.
In contrast, the placebo group’s DASS scores showed a slight increase by the end of the study. Notably, depression, anxiety, and stress scores all decreased in those taking spirulina, indicating broad mental health improvements.
Participants reported feeling less anxious and less stressed over the eight-week period. These psychological benefits align with the sleep improvements, as better sleep often goes hand-in-hand with better mood and lower stress.
Weight and blood pressure unchanged
Despite the positive effects on sleep and mood, spirulina supplementation did not significantly affect BMI and blood pressure in either group.
This suggested that the daily dose of spirulina did not lead to weight loss or gain or alter blood pressure in this short timeframe.
While previous reviews have hinted that spirulina might help manage hypertension, this trial did not find a blood pressure effect, possibly due to the relatively healthy baseline status of participants.
The stability of BMI is also notable for supplement manufacturers, indicating that adding spirulina for mood or sleep benefits likely won’t inadvertently cause weight changes.
High adherence, no serious side effects
Trial adherence was high, meaning participants consistently took their supplements as directed. Only two people in the spirulina group missed any doses (one day and three days out of 56 days in total), and 95% of the enrolled subjects completed the eight-week trial.
The spirulina softgel was well tolerated, with no severe adverse effects reported during the study.
Mild symptoms, if any, were not detailed, indicating that spirulina at two grams per day was generally safe in this population.
This safety profile, combined with high adherence, suggests spirulina could be a practical add-on therapy people are willing and able to take daily without major complaints.
Potential benefits of tryptophan
Spirulina’s positive effects on sleep and mood may be explained by its nutritional composition. Spirulina is naturally rich in tryptophan, an amino acid the body uses to produce serotonin and melatonin — chemicals in the brain that regulate mood and sleep-wake cycles.
By providing a dietary source of tryptophan, spirulina could help support the production of these calming, mood-stabilising compounds.
In fact, tryptophan-rich foods have been suggested as a way to improve insomnia by addressing one root cause of sleep disturbances.
Beyond tryptophan, spirulina also contains B vitamins, iron, magnesium, carotenoids, and antioxidants like phycocyanin and gamma-linolenic acid.
These nutrients have anti-inflammatory and antioxidant properties that might reduce stress and improve overall brain health. While the study did not measure biological markers, the authors note that spirulina’s complex of nutrients likely contributes to an integrated approach for stress control and sleep health.
Relevance for future research
The study authors suggested longer trials were needed to confirm and extend the aforementioned results, possibly including biological measures like blood biomarkers or hormone levels to understand how spirulina works.
Future research could explore higher doses, different populations (such as those with severe depression or anxiety disorders), or combine spirulina with other interventions.
They concluded: “Our study highlights two significant benefits of spirulina supplementation: improved sleep quality and latency, and decreased depression, anxiety, and stress scores. Therefore, supplementing with spirulina, a natural food supplement, is an option for increasing sleep quality and mental health. This is particularly beneficial for individuals with mild to moderately severe depression.”
Source: Food Science & Nutrition
“Effectiveness of an Arthrospira platensis (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”
https://doi.org/10.1002/fsn3.70082
Authors: Phenphop Phansuea, et al.
