In an assessment carried out on iodine-containing seaweed consumption in France the Agency found iodine levels in seaweed-based products varied according to how the seaweed is produced and processed.
Iodine levels were also dependent on the type of seaweed-based preparation (powder, extract) used in food supplements.
“Regular excessive intake of iodine can cause thyroid dysfunctions as well as certain adverse effects, particularly cardiac or renal effects,” ANSES said.
“The Agency therefore advises against the consumption of food and food supplements containing seaweed by people with thyroid dysfunction, heart disease or kidney failure, those taking medication containing iodine or lithium and pregnant or breastfeeding women, without seeking medical advice.”
ANSES’s concern stems from its findings that show iodine content in the various seaweed-based products can be high.
The Agency highlighted the possibility that its consumption presented a “non-negligible risk” of exceeding the upper intake levels, particularly if the seaweed was consumed in combination with seaweed-based food supplements.
Children in particular were vulnerable to the risks, as parents were reminded to exercise caution regarding their children's consumption of seaweed-based products, as there was insufficient data for measuring the risk involved.
In general, the Agency recommended that consumers chose supply channels regulated by the authorities for all seaweed-based foods and food supplements.
ANSES also reminded healthcare professionals of the need to report any adverse effects to its nutrivigilance scheme that could be associated with the consumption of food supplements.
ANSES report, dated June 25 2018 details the use of dietary supplements from algae, in which European Directive 2002/46 / EC regulates its use and consumption.
According ANSES, the consumption of food supplements in France increased from 20% to 29% when compared to the period previously evaluated.
ANSES also revealed that in 2015, dietary supplements for weight management represented 10% of sales in France, behind the transit segments (14%), sleep (14%) and energy (17%).
“Dietary supplements based on algae are in the segments "transit" and "slimming", whose sales account for nearly a quarter of dietary supplements sold in France in 2016,” the report said. “Women made up 35% of those consuming food supplements.”
The report also said that dietary supplements from algae are widely used as additives of dieting since algae contains large amounts of polysaccharides (alginates and carrageenan) that meet the definition of dietary fibre.
Their thickening nature explains their use as an "appetite suppressant" in this context.
“Beyond food supplements, given the changes in eating habits of French consumers, ANSES considers it necessary to conduct an investigation to determine precisely the frequency and mode of consumption of algae,” the report concluded.
“Moreover, ANSES would also have the results of the determination of the iodine content in seaweed when consumed as well as information concerning the botanical identity of the alga, the method for processing and its preparation method.
“This data will help to refine the exposure to iodine linked to different types of seaweed consumption for the populations concerned and, if necessary, reassess the limit of iodine content set for edible seaweed.”
ANSES's assessment was based on the tolerable upper intake level for iodine established by the European Food Safety Authority (EFSA) at 600 micrograms per day (µg/day) for adults and adjusted for each age group of consumers.
In addition, French regulations have laid down a maximum daily dose for iodine in food supplements of 150 µg.
EFSA’s list of the decree "plants" includes 540 plants that include 30 algae, micro-algae (cyanobacteria and microalgae, treated as "algae" by the public) and halophytes (greater maritime zones plants), which can be used in the formulation of dietary supplements.
The iodine content in these organisms can vary and the risk of exceeding regulatory limits iodine during their consumption is not negligible.