Blue-Green Algae

Blue-green algae are a group of bacteria. They can be used as a source of protein, but contain no more protein than meat or milk.

Blue-green algae produce blue-green colored pigments and are high in protein, iron, and other minerals. They grow in saltwater and some large freshwater lakes. They have been used for food for several centuries in Mexico and some African countries. In the US, they've been sold in supplements since the late 1970s.

People use blue-green algae for treating high blood pressure and as a protein supplement. It's also used for high levels of cholesterol or other fats (lipids) in the blood, diabetes, obesity, and many other conditions. But there is no good scientific evidence to support these other uses.

Some blue-green algae products are grown under controlled conditions. Others are grown in a natural setting, where they're more likely to be contaminated. Only use products that have been tested and are free of contaminants such as heavy metals, liver toxins called microcystins, and harmful bacteria. Don't confuse blue-green algae with other algaes, like Ascophyllum nodosum, Ecklonia cava, Fucus Vesiculosis, or Laminaria.

When taken by mouth: Blue-green algae products that are free of contaminants are possibly safe for most people when used short-term. Doses up to 19 grams daily have been used safely for up to 2 months. Lower doses of 10 grams daily have been used safely for up to 6 months. Side effects are typically mild and may include nausea, vomiting, diarrhea, headache, and dizziness.

But blue-green algae products that are contaminated are possibly unsafe. Contaminated blue-green algae can cause liver damage, vomiting, weakness, rapid heartbeat, shock, and death. Don't use any blue-green algae product that hasn't been tested and found to be free of microcystins and other contaminants.

Special Precautions & Warnings:

Blue-green algae has most often been used by adults in doses of 1-10 grams by mouth daily for up to 6 months. Only use products that have been tested and are free of contaminants such as heavy metals, liver toxins called microcystins, and harmful bacteria. Speak with a healthcare provider to find out what product and dose might be best for a specific condition.

AFA, Algae, Algas Verdiazul, Algues Bleu-Vert, Algues Bleu-Vert du Lac Klamath, Anabaena, Aphanizomenon flos-aquae, Arthrospira fusiformis, Arthrospira maxima, Arthrospira platensis, BGA, Blue Green Algae, Blue-Green Micro-Algae, Cyanobacteria, Cyanobactérie, Cyanophycée, Dihe, Espirulina, Hawaiian Spirulina, Klamath, Klamath Lake Algae, Lyngbya wollei, Microcystis aeruginosa and other Microcystis species, Nostoc ellipsosporum, Spirulina Blue-Green Algae, Spirulina fusiformis, Spirulina maxima, Spirulina platensis, Spiruline, Spiruline d'Hawaii, Tecuitlatl.

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