Spirulina, or blue-green algae, is used as a source of food in some parts of the world, but in the United States is more commonly sold as a supplemental source of protein, minerals and vitamins. Spirulina supplements should be obtained from a trusted source; it's important to be sure any spirulina you purchase is free from contamination so that it does not pose a danger to your health.
Definition
Spirulina is the primitive bacterium Cyanobacteria. Wild spirulina thrives as pond scum or lake algae, but it is cultivated in controlled environments for nutritional supplements. Of the more than 1,500 species of spirulina, some are safe to eat while others cause gastroenteritis and hepatitis.
Components
Spirulina is about 50 percent to 70 percent protein and provides all the essential amino acids. It contains vitamins A and E, niacin, folic acid, thiamine and choline, as well as the dietary minerals potassium, zinc, copper and magnesium. Other constituents include chlorophyll, and carbohydrates, including polysaccharides. Blue-green algae are a source of the heart-healthy omega-3 and omega-6 fatty acids.
Health Dangers
Serious adverse effects occur when spirulina becomes contaminated with microcystin. Microcystin is highly toxic and can result in liver damage, kidney failure, injured nervous tissue, seizures, respiratory arrest, acute pancreatitis and cardiomyopathy. When wild blue-green algae bloom they produce toxins that may be hazardous to humans and animals. Exposure to the blooms, whether by eating, contact with skin or inhalation, can cause skin or eye irritation, rashes, allergic reactions and gastrointestinal problems.
Drug Interactions
Spirulina may interact with medications that suppress the immune system, such as adalimumab, cyclosporine, etanercept and methotrexate. If you take medications, talk to your health care provider before consuming blue-green algae.
Warnings
People with phenylketonuria, or PKU, should never take spirulina, according to the University of Maryland Medical Center. You should also avoid blue-green algae if you have an autoimmune disease such as multiple sclerosis, rheumatoid arthritis or lupus because it could make your condition worse.
