Spirulina can help to lower blood pressure
High blood pressure occurs when the heart has to work twice or more as hard as it would normally take to pump blood throughout your body. This could be as a result of constricted blood vessels. The arteries take oxygenated blood away from the heart to other parts of the body and if these become smaller in diameter, the heart would have to pump harder. With high blood pressure, there is an increased risk of cardiovascular diseases, heart attack, cerebral infarction and chronic kidney disease.
Subjects with normal blood pressure managed to lower blood pressure with a daily dose of 4.5 grams (a big teaspoon) of spirulina (source 1, source 2)
Spirulina probably owes this effect on blood pressure to the production of nitric oxide (source 3). Nitric oxide ensures that blood vessels relax and widen to allow the free flow of blood.
Miczke et al. in 2016 (source 4) in a study showed an improvement in the systolic blood pressure (SBP) and stiffness index (SI) of overweight participants with high blood pressure. These results show how effective spirulina is at helping reduce stiffness of arteries and subsequently blood pressure in humans.
Source 1: Mazokopakis EE, Starakis IK, Papadomanolaki MG, Mavroeidi NG, Ganotakis ES. The hypolipidaemic effects of Spirulina (Arthrospira platensis) supplementation in a Cretan population: a prospective study. J Sci Food Agric. 2014;94(3):432‐437. doi:10.1002/jsfa.6261
Source 2: Torres-Duran, Patricia V et al. “Antihyperlipemic and antihypertensive effects of Spirulina maxima in an open sample of Mexican population: a preliminary report.” Lipids in health and disease vol. 6 33. 26 Nov. 2007, doi:10.1186/1476-511X-6-33
Source 3: Juárez-Oropeza MA, Mascher D, Torres-Durán PV, Farias JM, Paredes-Carbajal MC. Effects of dietary Spirulina on vascular reactivity. J Med Food. 2009;12(1):15‐20. doi:10.1089/jmf.2007.0713
Source 4: Miczke A, Szulińska M, Hansdorfer-Korzon R, 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.