Botanical
Algae
Algae are a diverse group of mostly aquatic organisms that live by photosynthesis, from single-celled microalgae such as chlorella to large seaweeds.
Seaweed can supply a lot of iodine
Kombu and wakame can contain substantially more iodine than nori. The amount varies with species and production, so a generic seaweed serving is a poor way to predict intake. BfR notes that just 1 to 2 g of iodine-rich dried kombu can supply several thousand micrograms of iodine. 1