Eat Your Algae: The Potential Benefits of Spirulina
By Boris Nagoda
Since the 1990s, Spirulina has been commonly available as a nutrition supplement at health food stores and supermarkets. Some sources consider Spirulina a “superfood” with remarkable health benefits. But what is Spirulina, and is there evidence to support these claims?
Spirulina is a generic name for several species of Arthospira, spiral-shaped, single-celled organisms known as cyanobacteria. Cyanobacteria (formerly called blue-green algae) are bacteria which, like plants, use photosynthesis to gather energy from sunlight. They are found in fresh and salt water worldwide. Although Spirulina organisms are tiny, they can grow so densely in warm lakes and ponds that they often appear as thick green mats on the surface of the water.
For centuries, Spirulina has been used as an important source of nutrients. It was harvested from lakes and ponds, dried, and eaten as cakes. In parts of Africa, writings about Spirulina date back to the 9th century, and in Mexico, 16th century conquistadors wrote of the Aztecs eating Spirulina cakes.
Today, Spirulina is sold in pellet, powder, or flake form, dried or freeze-dried, and is eaten raw or mixed with foods or beverages such as smoothies. Most Spirulina supplements are not wild-harvested, but are grown in indoor culture facilities or manmade ponds under controlled conditions. This practice eliminates possible contamination; Spirulina intended for human consumption must be grown in clean water, since it can be contaminated by heavy metals in the water or by microcystins, toxic compounds produced by other cyanobacteria. Numerous studies have shown that Spirulina itself is completely safe for human consumption.
Studies of Spirulina’s nutritional content have shown a very high protein content; Spirulina is composed of over 60% protein on average. The high protein content is due to the fact that Spirulina is rich in amino acids, including all the essential amino acids. Spirulina is also high in photosynthetic pigments called carotenoids, which are powerful antioxidants. Spirulina contains high amounts of vitamin E, fatty acids, and important minerals such as manganese, zinc, selenium and iron.
The high nutrient content of Spirulina provides proven benefits. Animal studies show that Spirulina consumption provides an immune-system boost, increasing the production of antibodies and other immune system components and strengthening overall resistance to disease.
In addition to enhancing immune system function, Spirulina may have other health benefits. Animal studies have suggested that Spirulina acts as a natural antihistamine, improving allergy symptoms such as watering eyes and runny nose. Compounds contained in Spirulina such as calcium spirulan, cyanovirin-N, and microvirin, have been shown in test tube studies to inactivate infectious viruses and inhibit their growth within cells.
Finally, substances in Spirulina may even have anti-cancer properties. One study in humans suggested that Spirulina supplements were responsible for reducing or removing precancerous lesions. Spirulina’s antioxidants may be responsible; it contains a fatty acid called gamma linolenic acid, which has been shown to kill cancer cells without harming normal cells. Research is ongoing in this exciting area.
While more studies of the health benefits of Spirulina in humans are needed, there is enough evidence from animal studies to suggest that the nutrients present in Spirulina have many beneficial effects. In the coming years, researchers might discover even more health benefits from this humble pond scum.