Risk of excessive iodine intake with certain algae products - Hidden Dangers: High Iodine in Algae Foods Lacks Warnings

A new study has revealed alarming iodine levels in some algae-based foods. Many products lack proper warnings or clear labelling, despite posing potential health risks. Consumer groups are now pushing for stricter regulations to protect buyers. Researchers analysed 13 algae-containing foods and found eight required safety warnings—but none complied. The study highlighted seven algae species: Arame, Kombu, Wakame, Hijiki, Nori, Uva, Spirulina, and Chlorella. Among these, Arame, Kombu, Wakame, and Hijiki showed extremely high iodine concentrations, ranging from 5,000 to 11,000 micrograms per gram of dry weight.

A rooibos tea containing kombu algae was flagged as particularly unsafe due to its iodine content. The product carried no warnings or serving size guidance. The German Federal Institute for Risk Assessment has long advised that high-iodine items should include clear labels and consumption limits.

Edible algae vary dramatically in iodine content, making accurate information crucial for consumers. Currently, many products fail to list iodine levels or suggest safe serving sizes. The German Nutrition Society recommends a daily intake of 150 micrograms, while exceeding 600 micrograms can harm thyroid function. Consumer advocates are now calling for legally binding iodine labelling on all algae products. They stress the need for mandatory warnings, serving size details, and clear iodine content information. Without these measures, buyers remain at risk of unintentionally consuming unsafe amounts.