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Blue-green Algae

  • Definition

    Blue-green algae supplements were introduced into the U.S. in 1979, with claims that they could aid weight loss and increase energy. Algae is sold as a nutritional supplement.



    Spirulina is a unicellular blue-green alga that has been consumed by man since ancient times in Mexico and Africa. It is currently grown in many countries by synthetic methods. Initially Spirulina was eaten for its nutritive value. It is a rich natural source of proteins, carotenoids, and other micronutrients.

    Recent preclinical testing suggests it may have immunological, antiviral and cholesterol-reducing therapeutic properties.

    In animal experiments for short-term and long-term toxicity, mutagenicity, and teratogenicity, the algae did not cause toxicity. The Spirulina administered to the animals in the studies were at much higher amounts than those expected in human consumption.

    Research in Japan has shown that the phycocyanin in spirulina raises lymphocyte activity and strengthens the immune system. In India and Germany, researchers have used spirulina to reduce cholesterol levels and to lower blood pressure in those with mild hypertension.

    Experimental studies in animal models have demonstrated an inhibitory effect of Spirulina algae on oral cancer, and this was also shown in a preliminary human study in India.


    Health Food stores carry a variety of spirulina products, including powder, granules and tablets. The powder can be added to drinks and other foods. A variety of health food contain spirulina, protein, chlorophyll, and minerals.

    Before consuming any nutritional supplement, talk to your physician about the risks and benefits for your particular medical condition.


    Do you recommend spirulina?

    Are there any side effects to taking spirulina?

    How often and how much spirulina is recommended?

    Does spirulina work best when taken with food? Are there any special instructions to taking spirulina?