Spirulina

Spirulina is the common name for a food supplement produced primarily from two species of cyanobacteria (also known as blue-green algae): Arthrospira platensis, and Arthrospira maxima. These and other Arthrospira species were once classified in the genus Spirulina.

There is no agreement that they are distinct genera, and that the food species belong to Arthrospira; nonetheless, the older term Spirulina remains the popular name.

Spirulina is cultivated around the world, and is used as a human dietary supplement as well as a whole food and is available in tablet, flake, and powder form.

Spirulina is believed to have been a food source for the Aztecs and other Mesoamericans until the 16th-century; its harvesting from Lake Texcoco and subsequent sale as cakes is described by one of Cortés' soldiers.

Nutrients and other chemicals

Protein

Spirulina contains an unusually high amount of protein, between 55% and 77% by dry weight, depending upon the source.

It is a complete protein, containing all essential amino acids. It is superior to typical plant protein, such as that from legumes.

Essential fatty acids

Spirulina is rich in gamma-linolenic acid (GLA), and also provides alpha-linolenic acid (ALA), linoleic acid (LA), stearidonic acid (SDA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA).

Vitamins

Spirulina contains:

• vitamin B1 (thiamine)
• B2 (riboflavin)
• B3 (nicotinamide)
• B6 (pyridoxine)
• B9 (folic acid)
• vitamin C
• vitamin D
• vitamin E.

A 2007 study found that 36 volunteers taking 4.5 grams of spirulina per day, over a six week period, exhibited significant changes in:

• cholesterol and blood pressure: lowered total cholesterol;
• increased HDL cholesterol;
• lowered triglycerides; and
• lowered systolic and diastolic blood pressure.