24 Nov General Recommendations
Spirulina has typically been studied in daily doses of 1 to 10g. Recommended dosage for adults (18 years and older): 3-10 g/day (**12, **13, **15).
Spirulina is considered nontoxic for health subjects at usual levels of consumption; however information is limited concerning interactions with pharmaceutical compounds or other dietary supplements.
Information regarding safety and efficacy in pregnancy and lactation is lacking. Few side effects have been reported from Spirulina including headache, stomach ache, muscle pain, flushing of the face, sweating and difficulty concentrations (9). If these intolerance symptoms persist, the consumption of Spirulina must to be stopped. A few cases of severe side-effects have been also reported including hepatotoxicity (10) and rabdomyolysis (**9).
Since Spirulina is a immunomodulatory supplement it might affect disease severity in patients with autoimmune diseases.
These patients have to avoid the consumption of Spirulina (**7, **8).
People with phenylketonuria should avoid the consumption of Spirulina (9).
It must be emphasized that one has to avoid the consumption of Spirulina of unknown origin or originated from countries which do not guarantee the quality and safety of the product.
The major areas of concern for safety are microbiological load, heavy metal content, pesticides, extraneous matter and cyanobacterial toxins (**11, **12).
Spirulina and Iodine
Upper safe levels for total daily intake (for a 60kg bodyweight adult) of Iodine established by the Scientific Committee on Food (SCF) and the European Food Safety Authority (EFSA) are 600 μg, while the corresponding value suggested by the US Institute of Medicine (IOM) is 1100μg (4).
Since the amount of iodine contained in 10g of dried Spirulina biomass is only 3 μg (5), (in contrast to seawater macro-algae which contain much higher iodine amounts (6) there is no risk for the consumer of in taking of excessive iodine.
(**) Literature on the subject