Spirulina is an alga that is bright green. It has been used as an antioxidant to slow damage to cells. Spirulina has also been used to help the body fight illness and lower cholesterol. It can be taken as a pill, powder, or extract. Spirulina can also be made into a tea.
2 to 5 grams daily
What Research Shows
May Be Effective
Not Enough Data to Assess
Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.
It is likely safe to take contaminant-free spirulina in small doses for a short time.D1, D2 Not enough studies have been done to say whether it is safe to use for a long period. It is also not known whether it is safe to take by women who are pregnant or breastfeeding.
Talk to your doctor about any supplements or therapy you would like to use. Some can interfere with treatment or make conditions worse.
A. Chronic Arsenic Poisoning
A1. Misbahuddin M, Islam AZ, et al. Efficacy of spirulina extract plus zinc in patients of chronic arsenic poisoning: a randomized placebo-controlled study. Clin Toxicol (Phila). 2006;44(2):135-141.
B. High Cholesterol
B1. Serban MC, Sahebkar A, et al. A systematic review and meta-analysis of the impact of Spirulina supplementation on plasma lipid concentrations. Clin Nutr. 2016;35(4):842-851.
C1. Miczke A, Szulińska M, et al. Effects of spirulina consumption on body weight, blood pressure, and endothelial function in overweight hypertensive Caucasians: a double-blind, placebo-controlled, randomized trial. Eur Rev Med Pharmacol Sci. 2016;20(1):150-156.
C2. Zeinalian R, Farhangi MA, et al. The effects of Spirulina Platensis on anthropometric indices, appetite, lipid profile and serum vascular endothelial growth factor (VEGF) in obese individuals: a randomized double blinded placebo controlled trial. BMC Complement Altern Med. 2017 Apr 21;17(1):225.
C3. Szulinska M, Gibas-Dorna M, et al. Spirulina maxima improves insulin sensitivity, lipid profile, and total antioxidant status in obese patients with well-treated hypertension: a randomized double-blind placebo-controlled study. Eur Rev Med Pharmacol Sci. 2017 May;21(10):2473-2481.
C4. Yousefi R, Mottaghi A, et al. Spirulina platensis effectively ameliorates anthropometric measurements and obesity-related metabolic disorders in obese or overweight healthy individuals: A randomized controlled trial. Complement Ther Med. 2018 Oct;40:106-112.
D1. Marles RJ, Barrett ML, et al. United States pharmacopeia safety evaluation of spirulina. Crit Rev Food Sci Nutr. 2011 Aug;51(7):593-604.
D2. Heussner AH, Mazija L, et al. Toxin content and cytotoxicity of algal dietary supplements. Toxicol Appl Pharmacol. 2012 Dec 1;265(2):263-71. doi: 10.1016/j.taap.2012.10.005. Epub 2012 Oct 12.
Last reviewed July 2019 by EBSCO NAT Review Board Eric Hurwitz, DC
Last Updated: 3/27/2020
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