Spirulina (Arthrospira platensis, Arthrospira maxima)
Lakes in tropical and subtropical climates. Waters most hospitable to spirulina have high concentrations of carbonate and bicarbonate, which produce the high pH environment in which spirulina thrives. There are two main species of spirulina. Arthrospira platensis is found in South America, Asia, and Africa; Arthrospira maxima is found only in Central America.
Numerous pigments, including carotenoids, chlorophyll-a, phycocyanin, and allophycocyanin; protein; lipids; vitamins B1,B2, B3, B6, B9, and vitamins A, C, D, and E; essential and trace minerals including potassium, calcium, magnesium, manganese, and selenium.
Spirulina is a microscopic blue-green alga from the genus Arthrospira that floats on the surface of lakes and ponds. Spirulina is spiral and threadlike in form. It grows in tropical and subtropical lakes with an alkaline pH.
At the time of the Spanish conquest, spirulina (Arthrospira maxima) was a traditional food of the Aztecs. One of Cortez’s soldiers noted how the Aztecs obtained and used this substance, describing “small cakes made from a sort of a ooze which they get out of the great lake”1 (Lake Texcoco, near what is now Mexico City). The native peoples called this substance tecuitlatl. Since the historical record makes no further mention of tecuitlatl after the conquest, historians believe that its use greatly diminished or died out in the sixteenth century.
Four hundred years later, in 1940, another species of spirulina, Arthrospira platensis, caught the attention of a French botanist. Working in Chad, the botanist observed the locals harvesting floating algae from lakes, drying it into cakes called dihe, and eating it.2 Spirulina harvested the traditional way remains an important part of the local economy around Lake Chad. The algae is collected, filtered, and dried. It is then cut into cakes and sold to both locals and to wholesalers.
This traditional method, however, is dwarfed by commercial production, which began in the 1970s. Most commercial spirulina is cultivated in shallow, artificial “raceway” ponds. It is grown in regions with temperate weather and a sunny climate, including Greece, the United States, Japan, Thailand, Spain, China, and India.
Spirulina has been granted GRAS (Generally Recognized As Safe) status from the U.S. Food and Drug Administration. Because it is so nutrient dense, it has great potential as a food source and as a nutritional supplement. Even NASA has investigated its potential as a nutrient-dense food source that can be grown in space. It has been included in astronauts’ diets during space missions.3
When dried, spirulina contains roughly 60% protein, and is considered superior to other plant proteins. It is 7% fat, including healthy fats such as gamma-linolenic acid (GLA), alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). It contains numerous B vitamins, as well as vitamins A, C, D, and E, and essential and trace minerals. The focus of much research, however, is on spirulina’s pigments, which research reveals to have numerous beneficial effects. It is particularly rich in carotenoids, including beta carotene and zeaxanthin. Researchers have discovered that 4.5 mg of beta carotene from spirulina produces the same vitamin A activity as 1 mg of retinyl acetate.4
One of the key benefits of spirulina is its antioxidant effect. One particular protein in spirulina, the pigment phycocyanin, has been identified as the key constituent responsible for its antioxidant effects.5 In vitro studies have demonstrated spirulina’s ability to reduce oxidation6 and protect cells from damage by free radicals.7 In animal models, spirulina raises plasma antioxidant capacity.8 Studies also demonstrate spirulina’s natural anti-inflammatory activity. Animal research demonstrates that spirulina (most likely its protein, phycocynanin) can inhibit the inflammatory disease process in non-alcoholic steatohepatitis (NASH).9 Spirulina also helps reverse the inflammatory process that leads to arthritis, according to studies in mice.10, 11
Cardiovascular health can also benefit from spirulina. In clinical trials, study participants were given spirulina for several weeks. Their triglycerides, total cholesterol, LDL cholesterol, and blood pressure all showed healthy, statistically significant reductions.12 In another clinical study, researchers looked at the effects of spirulina on the cholesterol and triglycerides of healthy young runners, again finding significant benefits.13 Rat studies suggest that spirulina’s favorable impact on cholesterol is because it suppresses cholesterol absorption and promotes greater excretion of cholesterol and bile acids.14
Spirulina can normalize blood sugar levels and protect the liver in animal models involving elevated blood sugar and fatty liver.15,16 Spirulina’s liver protection also extends to chronic hepatitis C. In a clinical trial, hepatitis patients given spirulina showed significant or total viral load decreases over the course of the six-month study. Spirulina was even more effective than silymarin, which has long been known to protect the liver.17 This blue-green algae also shows promise as a cancer preventative. In one animal experiment, researchers induced liver cancer in rats. Those who received spirulina had one-fourth the incidence of liver tumors compared to rats who did not received spirulina.18
One of the most exciting areas of spirulina research is on brain aging, brain health, and neurodegenerative disease. In one experiment with rats, researchers looked at spirulina’s ability to protect brain progenitor cells from acute inflammation and found it to be effective.19 In another rat experiment, spirulina was shown to protect the brain from damage due to Parkinson’s disease.20 In a study of mice with markers of Alzheimer’s disease, spirulina decreased the amount of amyloid beta protein deposits and exhibited antioxidant activity. Although further research is needed, the study findings indicate that spirulina may be beneficial for preventing or treating memory loss in Alzheimer’s patients.21
1 Ciferri, O. Spirulina, the edible microorganism. Microbiological Reviews. 1983, 47 (4), p. 551-552.
2 Ciferri, O. Spirulina, the edible microorganism. Microbiological Reviews. 1983, 47 (4), p. 551.
3 Karkos, P.D., et al. Spirulina in clinical practice: Evidence-based human applications. Evidence-Based Complementary and Alternative Medicine. 2011. Article ID 531053.
4 Wang, J., et al. Vitamin A equivalence of spirulina beta-carotene in Chinese adults as assessed by using a stable-isotope reference method. American Journal of Clinical Nutrition. 2008. 87, 1730-1737.
5 Pinero Estrada, J.E., et al. Antioxidant activity of different fractions of Spirulina platensis protean extract. Il Farmaco. 2001. 56, 497-500.
6 Miranda, M.S., et al. Antioxidant activity of the microalga Spirulina maxima. Brazilian Journal of Medical and Biological Research. 1998. 31: 1075-1079.
7 Chu, W.L., et al. Protective effect of aqueous extract from Spirulina platensis against cell death induced by free radicals. BMC Complementary and Alternative Medicines. 2010. 10:53.
8 Miranda, M.S., et al. Antioxidant activity of the microalga Spirulina maxima. Brazilian Journal of Medical and Biological Research. 1998. 31: 1075-1079.
9 Pak, W., et al. Anti-oxidative and anti-inflammatory effects of spirulina on rat model of non-alcoholic steatohepatitis. Journal of Clinical Biochemistry and Nutrition. 2012. 51 (3), 227-234.
10 Rasool, M., et al. Anti-inflammatory effect of Spirulina fusiformis on adjuvant-induced arthritis in mice. Biological & Pharmaceutical Bulletin. 2006. 29 (12), 2483-2487.
11 Ramirez, D., et al. Inhibitory effects of Spirulina in zymosan-induced arthritis in mice. Mediators of Inflammation. 2002. 11, 75-79.
12 Torres-Duran, P.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. 2007. 6:33.
13 Torres-Duran, P.V., et al. Effect of Spirulina maxima on postprandial lipemia in young runners: A preliminary report. Journal of Medicinal Food. 2012. 15 (8), 753-757.
14 Nagaoka, S., et al. A novel protein C-phycocyanin plays a crucial role in the hypocholesterolemic action of Spirulina platensis concentrate in rats. The Journal of Nutrition. 2005. 135: 2425–2430.
15 Jarouliya, U., et al. Alleviation of metabolic abnormalities induced by excessive fructose administration in Wistar rats by Spirulina maxima. Indian Journal of Medical Research. 2012. 135 (3), 422-428.
16 Moura, L.P., et al. Exercise and spirulina control non-alcoholic hepatic steatosis and lipid profile in diabetic Wistar rats. Lipids in Health and Disease. 2011. 10:77.
17 Yakoot, M., and Salem, A. Spirulina platensis versus silymarin in the treatment of chronic hepatitis C virus infection: A pilot randomized, comparative clinical trial. BMC Gastroenterology. 2012. 12 (32).
18 Ismail, M.F. Chemoprevention of rat liver toxicity and carcinogenesis by Spirulina.International Journal of Biological Sciences. 2009. 5 (4), 377-387.
19 Bachstetter, A., et al. Spirulina promotes stem cell genesis and protects against LPS-induced declines in neural stem cell proliferation. PLoS ONE. 2010. 5 (5).
20 Pabon, M.M., et al. A Spirulina-enhanced diet provides neuroprotection in an alpha–synuclein model of Parkinson’s disease. PLoS ONE. 2012. 7 (9).
21 Hwang, J.H., et al. Spirulina prevents memory dysfunction, reduces oxidative stress damage, and augments antioxidant activity in senescence-accelerated mice.Journal of Nutritional Science and Vitaminology. 2011. 57, 186-191.
1. Anti-oxidative and anti-inflammatory effects of spirulina on rat model of non-alcoholic steatohepatitis
Pak, W., et al. Journal of Clinical Biochemistry and Nutrition. 2012. 51 (3), 227-234.
In this animal study, researchers examined the effects of spirulina on rats with non-alcoholic steatohepatitis (NASH). NASH was induced in rats and as expected, the rats showed increased liver enzymes and fibrosis, as well as elevated markers for oxidation and increased immune system response. Rats who were given spirulina had less liver enzyme elevation, less liver fibrosis, and fewer activated immune system markers. Based on these results, researchers conclude that spirulina or phycocyanin, a pigment-protein complex found in spirulina, shows promise as a therapeutic treatment to stop or slow NASH.
2. Anti-inflammatory effect of Spirulina fusiformis on adjuvant-induced arthritis in mice
Rasool, M., et al. Biological & Pharmaceutical Bulletin. 2006. 29 (12), 2483-2487.
Researchers induced arthritis in the paws of mice. Compared to the control mice, the arthritic mice showed increased paw volume and increased levels of lysosomal enzymes, tissue marker enzymes, and glycoproteins. Spirulina fusiformis was administered to the arthritic mice for eight days and they were then reexamined. The arthritic markers reversed to nearly pre-arthritic levels. The researchers conclude that Spirulina fusiformis has potential as an anti-inflammatory agent.
3. Antihyperlipemic and antihypertensive effects of Spirulina maxima in an open sample of Mexican population: A preliminary report
Torres-Duran, P.V., et al. Lipids in Health and Disease. 2007. 6:33.
In this clinical trial, researchers looked at the effects of orally supplemented Spirulina maxima on blood lipids, blood sugar, blood pressure, and aminotransferases. Study participants did not adhere to any special diet during this trial. At the beginning and at the end of the study, blood tests were taken for a variety of markers, including blood sugar, triglycerides, cholesterol, and aspartate aminotransferase (AST). Blood pressure was also recorded. Trial results showed beneficial changes in triglycerides, total cholesterol, and LDL cholesterol. Subjects’ blood pressure also showed statistically significant decreases. Researchers conclude that Spirulina maxima reduced blood lipids and blood pressure, bringing them both to more beneficial levels.
4. Alleviation of metabolic abnormalities induced by excessive fructose administration in Wistar rats by Spirulina maxima
Jarouliya, U., et al. Indian Journal of Medical Research. 2012. 135 (3), 422-428.
In this study, researchers looked at the potential of Spirulina maxima to mitigate the effects of a high fructose diet in rats. Rats were fed fructose for 30 days in order to induce high blood sugar and hyperlipidemia (an excess amount of fats in the blood). During the 30-day period, rats were also fed a liquid suspension (either 5% or 10%) of Spirulina maxima daily. Compared to control groups, rats fed both the 5% and 10% spirulina suspensions showed significant reductions in blood sugar and liver function markers; lipid profiles also showed significant improvements. Researchers conclude that Spirulina maxima may have a protective effect against the metabolic effects of a high fructose diet.
5. Antioxidant activity of different fractions of Spirulina platensis protean extract
Pinero Estrada, J.E., et al. Il Farmaco. 2001. 56, 497-500.
In this study, researchers looked closely at phycocyanin, one of the proteins found in Spirulina platensis. The researchers purified the phycocyanin in order to obtain and test different fractions. They discovered that the higher the phycocyanin content, the greater the antioxidant power of the various fractions. Thus, they concluded that the antioxidant effects of spirulina can primarily be attributed to phycocyanin.
6. Chemoprevention of rat liver toxicity and carcinogenesis by spirulina
Ismail, M.F. International Journal of Biological Sciences. 2009. 5 (4), 377-387.
This rat study examined whether Spirulina platensis could protect the liver against toxicity and cancer. Researchers administered cancer-causing agents to rats, which caused severe liver injury and signs of disease in the liver tissue. Rats who received only the cancer-causing agent had an 80% incidence of liver tumors. Rats who also received spirulina had only a 20% incidence of liver tumors. Further tests revealed that spirulina suppressed the disease process, including inhibition of cell proliferation and induction of apoptosis (cell death). Researchers believe these results may suggest spirulina as a potential cancer preventative.
7. Protective effect of aqueous extract from Spirulina platensis against cell death induced by free radicals
Chu, W.L., et al. BMC Complementary and Alternative Medicines. 2010. 10:53.
Researchers used chemical assays and cell-based assays to examine the antioxidant activity of spirulina extract. Mouse fibroblasts were exposed to either spirulina or vitamin C, and then free radicals were added to the medium to induce cell death. Although the spirulina extract significantly lessened cell death according to one test, vitamin C was more effective. A second test method showed that the spirulina extract has the same level of antioxidant activity as vitamin C. Researchers conclude that spirulina extract is effective against cell death caused by free radicals and worthy of further investigation.
8. Antioxidant activity of the microalga Spirulina maxima
Miranda, M.S., et al. Brazilian Journal of Medical and Biological Research. 1998. 31: 1075-1079.
In this study, researchers conducted both in vitro and in vivo experiments to evaluate the antioxidant capacity of Spirulina maxima extract. In the in vitro experiment, researchers found that an extract of spirulina reduced oxidation of a brain homogenate by 50%. In the in vivo experiment, researchers gave animals spirulina for several weeks and then looked at the antioxidant capacity in their plasma and livers. While liver antioxidant capacity was similar in both the spirulina group and the control group, plasma antioxidant capacity was 71% in the spirulina group as compared to just 54% in a control group.The researchers concluded that spirulina provides antioxidant protection.
9. Molecular study of dietary heptadecane for the anti-inflammatory modulation of NF-kB in the aged kidney
Kim, D.H., et al. PLoS ONE. 2013. 8(3): e59316.
Researchers looked at the effect of heptadecane, a component of Spirulina platensis, to mitigate inflammation. The study focused on the NF-kB pathway, a process that, when it goes awry, is associated with autoimmune and inflammatory diseases, cancer, infection, and other health problems. Rats were given heptadecane over a period of ten days and rat kidney tissue was examined for changes. Results revealed that the heptadecane had a significant antioxidant effect and weakened the activity of NF-kB along a specific metabolic pathway.
10. Spirulina platensis versus silymarin in the treatment of chronic hepatitis C virus infection. A pilot randomized, comparative clinical trial
Yakoot, M., and Salem, A. BMC Gastroenterology. 2012. 12 (32).
In this six-month clinical study, researchers examined whether Spirulina plantensis had any potential therapeutic effect for patients suffering from chronic hepatitis C virus. The participants were divided into two groups. One group received spirulina treatment; the other group received silymarin treatment. Participants were tested at the three-month point and again at six months. In the spirulina group, 20% of participants had either a significant or total viral load decrease. Other markers also indicated that spirulina treatment was more effective than silymarin. Researchers conclude that based on the results of this small trial, further research is warranted to explore spirulina’s therapeutic potential in chronic hepatitis C.
11. Exercise and spirulina control non-alcoholic hepatic steatosis and lipid profile in diabetic Wistar rats
Moura, L.P., et al. Lipids in Health and Disease. 2011. 10:77.
Researchers looked at the effects of exercise and spirulina on diabetic rats with non-alcoholic fatty liver disease. Rats were divided into four groups: diabetic rats who were given neither spirulina nor exercise (the control group); diabetic rats who were given spirulina but no exercise; diabetic rats who were given both spirulina and exercise; and diabetic rats who were given exercise but no spirulina. Only the control group achieved no benefit. The other three groups all had lower LDL cholesterol and lower levels of fats in the liver. Researchers conclude that spirulina, with or without exercise, is helpful in reducing LDL cholesterol and fats in the liver.
12. Spirulina prevents memory dysfunction, reduces oxidative stress damage, and augments antioxidant activity in senescence-accelerated mice
Hwang, J.H., et al. Journal of Nutritional Science and Vitaminology. 2011. 57, 186-191.
Researchers looked at the effects of spirulina on markers of brain aging in mice. Mice were divided into three groups: a control group, a group given lower doses of spirulina, and a group given higher doses of spirulina. Both spirulina groups showed fewer amyloid beta protein deposits (which are associated with Alzheimer’s disease) in the hippocampus and throughout the brain. Levels of lipid peroxidation were also lower in various parts of the brain for those groups. The mice given higher amounts of spirulina also demonstrated increased catalase activity, an antioxidant process that protects cells. Researchers conclude that spirulina may be of therapeutic or preventative use for memory loss associated with Alzheimer’s disease.
13. Spirulina promotes stem cell genesis and protects against LPS-induced declines in neural stem cell proliferation
Bachstetter, A., et al. PLoS ONE. 2010. 5 (5).
This study examined the potential protective effect of spirulina on stem cells. Researchers looked specifically at its effect on protecting brain progenitor cells in rats from acute inflammation. Inflammation was induced in the brains of rats, and the rats were then euthanized so their brain tissue could be examined. In the brains of rats who consumed no spirulina spirulina, there were fewer stem/progenitor cells compared to the brains of rats who consumed spirulina for 30 days. Researchers also conducted further experiments (in vitro) looking at the effects of nutritional supplements, including spirulina, on bone marrow cells. Results demonstrated that while spirulina alone was somewhat beneficial, when used with a formula containing blueberry, green tea, vitamin D3, and carnosine, the nutrients protected stem cells and promoted their growth.
14. Improvement of mercuric chloride-induced testis injuries and sperm quality deteriorations by Spirulina platensis in rats
El-Desoky, G.E., et al. PLoS ONE. 2013. 8 (3).
In this in vivo study, researchers examined the role of Spirulina platensis in protection of rat testis. When mercury chloride was used to induce oxidative stress in a control group of rats, key markers of antioxidant activity decreased, suggesting they were inhibited by the mercury chloride. Sperm count, motility, and testosterone levels also decreased. Abnormally formed sperm and the level of mercury in the testis increased. Disease-induced changes to the structure of the testis were also observed. In contrast, rats who were treated with spirulina beforehand exhibited far less structural damage and less mercury accumulation. Antioxidant activity was not suppressed. Researchers conclude that Spirulina platensis may offer therapeutic benefits in mammals, and may be of particular interest in cases of heavy metal toxicity.
15. A novel protein C-phycocyanin plays a crucial role in the hypocholesterolemic action of Spirulina platensis concentrate in rats
Nagaoka, S., et al. The Journal of Nutrition. 2005. 135: 2425–2430.
Prior research shows that Spirulina platensis has a cholesterol lowering effect. This in vitro and in vivo rat study examined the issue further to determine the exact mechanism and the specific protein responsible for this effect. Spirulina suppressed cholesterol solubility and uptake, and had a greater bile acid binding capacity, in vitro compared to controls. In vivo, rats who consumed spirulina excreted more cholesterol and bile acids than rats fed a control diet. They also had lower levels of cholesterol in the liver and blood. Researchers also tested C-phycocyanin, a protein in spirulina, and found it to be even more effective. Researchers conclude that spirulina and more specifically C-phycocyanin may lower cholesterol by inhibiting its absorption in the intestine.
16. Spirulina prevents atherosclerosis by reducing hypercholesterolemia in rabbits fed a high cholesterol diet
Cheong, S.H., et al. Journal of Nutritional Science and Vitaminology. 2010. 56, 34-40.
In this study, rabbits were fed a high cholesterol diet for four weeks to induce high cholesterol, and then were given Spirulina platensis (along with the high cholesterol diet) for an additional eight weeks. Compared to a control group total cholesterol, LDL cholesterol, and triglycerides were all reduced in the rabbits fed spirulina, while HDL cholesterol increased. In addition, control group rabbits had thickening of the intimal surface (lining) of the aorta, which was significantly reduced in the spirulina-fed rabbits. Researchers conclude that spirulina may be effective at reducing high-cholesterol related atherosclerosis and its associated risk factors (high triglyerides, high LDL cholesesterol, high total cholesterol, and low HDL cholesterol).
17. Inhibitory effects of spirulina in zymosan-induced arthritis in mice
Ramirez, D., et al. Mediators of Inflammation. 2002. 11, 75-79.
In this study, researchers induced arthritis in mice and then fed the animals spirulina. The synovial (joint) fluid was examined for levels of beta glucuronidase (a marker for arthritis) and the joints examined for signs of disease. Spirulina decreased the levels of beta glucuronidase and inhibited inflammation. No evidence of cartilage damage or other indicators of disease were observed. Researchers note that these results may be due to the anti-inflammatory, antioxidant effects of phycocyanin, a protein found in spirulina.
18. Vitamin A equivalence of spirulina beta-carotene in Chinese adults as assessed by using a stable-isotope reference method
Wang, J., et al. American Journal of Clinical Nutrition. 2008. 87, 1730-1737.
In this human study, researchers looked at the vitamin A activity of spirulina compared to the vitamin A activity of retinyl acetate. Spirulina contains carotenoids, precursors of vitamin A. Healthy, normal weight men who normally consumed a low vitamin A diet were chosen for this study. They first ate a breakfast supplemented with retinyl acetate. A week later, they ate a breakfast supplemented with spirulina. Blood samples were then collected over a period of eight weeks to determine how much spirulina must be consumed in order to produce the equivalent vitamin A activity of retinyl acetate. The data showed that in this group of men, 4.5 mg of spirulina beta carotene produced the same vitamin A activity as 1 mg of retinyl acetate.
19. Effect of Spirulina maxima on postprandial lipemia in young runners: A preliminary report
Torres-Duran, P.V., et al. Journal of Medicinal Food. 2012. 15 (8), 753-757.
In this clinical trial, researchers examined the effects of Spirulina maxima on triglyceride levels of healthy young runners. Blood samples were taken, and then study participants consumed spirulina daily for 15 days. Then they were given a high fat meal after a period of fasting. Fasting blood levels of triglycerides were lower after 15 days of spirulina consumption. Post-meal blood levels of triglycerides were also lower after spirulina, as compared with the start of the trial.
20. A spirulina-enhanced diet provides neuroprotection in an alpha–synuclein model of Parkinson’s disease
Pabon, M.M., et al. PLoS ONE. 2012. 7 (9).
Because inflammation is associated with neurodegenerative diseases, researchers looked at spirulina’s potential benefit in inhibiting the activity of microglia, specialized immune cells of the brain and spinal fluid. For one month, rats were fed either a control diet or a diet supplemented with spirulina. Parkinson’s disease was then induced in the rats and their tissues were examined for lesions and microglial activity. Test results showed that rats who consumed spirulina had fewer activated microglia; thus, spirulina helped protect the brain.