Article - Effects of Spirulina supplementation in patients with ulcerative colitis: a double-blind, placebo-controlled randomized trial.

Expert Review

Reviewer: Chloe Steele

10th Jun 2024

Conflict of interest

None

Take home message

SP supplementation at 500 mg twice daily for 8 weeks may improve antioxidant status in individuals with UC; however, it is insufficient to have any effect on disease severity.

Evidence category

A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)

Summary review

Introduction - aim of study

Inflammation is part of the pathophysiology of ulcerative colitis (UC).
Anti-inflammatories and immunosuppressants are commonly used as treatments for UC, however there are safety concerns with their continued use.
The use of safer therapies would be preferable, and Spirulina (SP) has emerged as having anti-inflammatory properties that may be of benefit to people with UC.
This study aimed to determine the effect of SP supplementation on individuals with UC and its associated health complications.

Methods

This was an 8-week double-blind, placebo controlled, randomised control trial of 80 individuals with mild to moderate UC aged 18-65 years.
Participants were assigned to SP 500mg twice per day, before lunch and dinner, or placebo.
The level of disease activity was assessed and measured using the simple clinical colitis activity index (SCCAI).
Quality of life (QoL) was assessed using the Short Irritable Bowel Disease Questionnaire (SIBDQ).
Biomarkers of inflammation were assessed from blood and serum samples.

Results

73 individuals completed the study; dropouts were not due to the study compound. In the 73 individuals, compliance was >90% for both SP and placebo.
SP supplementation increased blood protein and iron levels (β = 1.22, 95% CI (0.87, 1.60), Large effect size ES Partial Eta Squared = 0.41 and (β = 1.16, 95% CI (0.56, 1.76), Large effect size ESPartial Eta Squared =0.17 respectively).
Within group comparisons showed that SIBDQ score improved regardless of whether given SP or placebo (P=<0.001 and P=0.012 respectively) but had no effect on the disease activity (SCCAI score; P=>0.05).
Compared to placebo, SP supplementation improved serum total antioxidant capacity (β = 0.83, 95% CI (0.60, 1.10), Large effect Size (Partial Eta Squared) = 0.37).
However, the biomarkers of inflammation, superoxide dismutase, malondialdehyde, PTX-3, and erythrocyte sedimentation rate, all remained unchanged with SP supplementation.

Conclusion

The study concluded that SP supplementation improved antioxidant status and QoL.

Clinical practice applications

Although the paper concluded that QoL was improved, this was based on within group comparisons and individuals in both the treatment and placebo groups reported improved QoL. It is not apparent if SP improved QoL over and above that of placebo.
Practitioners could use this paper to understand that SP supplementation of 1000mg per day split in two and delivered at lunch and dinner may improve antioxidant status, however it is apparent that there is no effect on disease severity.

Considerations for future research

As antioxidant status was improved, it may be worth looking at different biomarkers of inflammation such as inflammatory cytokines to determine if they are affected by SP supplementation.
It would also be worth understanding if longer study periods may affect disease severity given that antioxidant status is improved.

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Abstract

AIM

We conducted a randomized placebo-controlled trial to assess the efficacy of Spirulina (SP) supplementation on disease activity, health-related quality of life, antioxidant status, and serum pentraxin 3 (PTX-3) levels in patients with ulcerative colitis (UC).

METHODS

Eighty patients with UC were randomly assigned to consume either 1 g/day (two 500 mg capsules/day) of SP (n = 40) or control (n = 40) for 8 weeks. Dietary intakes, physical activity, disease activity, health-related quality of life, antioxidant status, erythrocyte sedimentation rate (ESR), and serum PTX-3 levels were assessed and compared between groups at baseline and post-intervention.

RESULTS

Seventy-three patients (91.3%) completed the trial. We observed increases in serum total antioxidant capacity levels in the SP supplementation group compared to the control group after 8 weeks of intervention (p ≤ 0.001). A within-group comparison indicated a trend towards a higher health-related quality of life score after 8 weeks of taking two different supplements, SP (p < 0.001) and PL (p = 0.012), respectively. However, there were no significant changes in participant's disease activity score in response to SP administration (p > 0.05). Similarly, changes in ESR and PTX-3 levels were comparable between groups post-intervention (p > 0.05).

CONCLUSIONS

SP improved antioxidant capacity status and health-related quality of life in patients with UC. Our findings suggest that SP supplementation may be effective as an adjuvant treatment for managing patients with UC. Larger trials with longer interventions periods are required to confirm our findings.