The safety of use of spirulina, used as a food or dietary supplement, is primarily based on the quality of its production, in order to prevent contamination by cyanotoxins, bacteria or by metal trace elements (see recent recommendations of the National Agency of Food Safety (ANSES). For more information on the quality control system provided by Antenna-France, see the corresponding chapter on this site.
In the United States, the FDA, through the “United States Pharmacopoeia Safety Evaluation”, has concluded after analysis of the very large non-clinical data, a lack of toxicity of Spirulina at the usual consumption doses.
In case of prolonged intake, there is no risk of overdose in vitamin A. Indeed spirulina brings pro-vitamin A or beta-carotene which is converted into vitamin A according to the body needs.
Side effects are very rare and in the majority of the cases, there are mild. These are mainly digestive disorders, muscle pain and allergic reactions. It should be noted that the review of the literature of controlled studies in malnourished infants and children found no adverse effects.
TO AVOID UNDESIRABLE EFFECTS, SOME SIMPLE RULES SHOULD BE FOLLOWED:
* If allergic symptoms occur during the first intake of spirulina: never resume.