Spirulina is a type of blue-green algae found in most lakes and ponds. It has been consumed for thousands of years by Mexican (Aztecs, Mayans), African, and Asian peoples. Spirulina is considered a complete protein because well over half of it consists of amino acids -- the building blocks of protein. It is also a rich source of other nutrients including B complex vitamins, beta-carotene, vitamin E, carotenoids, manganese, zinc, copper, iron, selenium, and gamma linolenic acid (an essential fatty acid). In fact, at least one laboratory study has demonstrated that the iron level in spirulina is equivalent to that contained in beef. Because of its apparent ability to stimulate the immune system, spirulina may have antiviral and anticancer effects. Test tube and animal studies suggest that spirulina may also help protect against harmful allergic reactions. More research is needed to fully understand how spirulina truly benefits people. 

Interestingly, spirulina has been used in Russia to treat the victims, especially children, of the nuclear disaster at Chernobyl. In these children, whose bone marrow had been damaged from radiation exposure, spirulina seemed to boost the immune system.

Immune Enhancement
Animal and test tube studies suggest that spirulina increases production of antibodies, cytokines (infection fighting proteins), and other cells that improve immunity and help ward off infection and chronic illnesses such as cancer.

Protein Supplement
Amino acids make up 62% of spirulina. Because it is a rich source of protein and other nutrients, spirulina has been used traditionally as a nutritional supplement by people who cannot obtain sufficient calories or protein through diet alone and by those whose nutritional requirements are higher than normal, such as athletes.

Anemia
Animal studies suggest that spirulina promotes hematopoiesis (formation and development of red blood cells). This is thought to be due to the high levels of iron present in this food supplement.

Allergic Reactions
Animal and test tube studies suggest that spirulina may protect against allergic reactions by preventing the release of histamines (substances that contribute to allergy symptoms such as a runny nose, watery eyes, hives, and soft-tissue swelling). Whether these preliminary studies will translate into benefit for people with allergies is not known.

Antibiotic-related Illnesses
Although antibiotics destroy unwanted organisms in the body, they may also kill "good" bacteria called probiotics (such as Lactobacillus acidophilus) which sometimes results in diarrhea. In test tubes, spirulina has promoted the growth of L. acidophilus and other probiotics. Whether this positive laboratory finding will translate into protection from antibiotic-related diarrhea is not clear at this time.

Infection
Test tube studies suggest that spirulina has activity against herpes, influenza, cytomeglovirus, and human immunodeficiency virus (HIV). Whether this laboratory finding will prove beneficial for people in treating these infections is not clear.

Oral Cancer
In one study, 87 people who chewed tobacco and had a precancerous lesion known as leukoplakia were randomly assigned to receive Spirulina fusiformis or placebo. Lesions were significantly more likely to disappear in the spirulina group than in the placebo group. More research in this area will be very helpful.

Liver Disorders
There is some preliminary evidence that spirulina may help protect against liver damage and cirrhosis (liver failure) in those with chronic hepatitis. More research is needed in this area.

Other
Spirulina is also contained in some skin care products due to its moisturizing and tightening properties, and components derived from spirulina may have properties to help reduce inflammation in, for example, arthritis. More research is needed in this latter area.

Spirulina is a microscopic algae that flourishes in warm climates and warm alkaline water. It is available dried and freeze-dried.

Spirulina is available in pill or powder form. Most of the spirulina consumed in the United States is cultivated in a laboratory. There are many different spirulina species (spp.), only some of which are identified on labels of commercially available products. Spirulina maxima (cultivated in Mexico) and Spirulina platensis (cultivated in California) are the most popular.

Pediatric

Although spirulina has been used in children (e.g. victims of the Chernobyl nuclear accident), the safe and effective dose for those under 18 has not yet been established.

Adult

Consult an appropriate health care provider for the correct dosage of spirulina. A standard dosage of spirulina is 4 to 6 tablets (500 mg each) per day.

Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable healthcare provider.

There are no known toxicities associated with spirulina, based on testing of high doses of this supplement in animals. Spirulina has even been tested in pregnant animals and no risk to either maternal or fetal rats and mice was discovered. However, it is not known whether this will translate to humans. Therefore, it is safest to talk with your health care provider before taking spirulina if you are pregnant or breast-feeding.

In addition, those with a metabolic condition called phenylketonuria (PKU) should discuss potential use of spirulina with their healthcare provider. This unusual condition is characterized by an inability to metabolize the amino acid phenylalanine. Spirulina is rich in all amino acids, including phenylalanine. Most likely, it is okay for those with PKU to use this supplement because the presence of all of the other essential amino acids balances the high levels of phenylalanine. However, it is best and safest to check with your healthcare provider if you have PKU.

There are no reports in the scientific literature to suggest that spirulina interacts with any conventional medications.

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