With algae, the entire nutrient richness of the sea comes in concentrated form on the plate: They consist of 30 percent protein and contain a lot of vitamin C, iron and calcium. Algic acid in brown algae can bind toxins in the body and thus supports the intestine. The top ingredient, however, is iodine, which is needed for the formation of thyroid hormones. 100 grams of fresh algae contain about 50 micrograms of iodine, in dried form is a multiple. Therefore, caution is advised: Too much iodine can lead to an overactive thyroid. A daily dose of 180 to 200 micrograms of iodine is recommended, with a maximum of 500. Algae preparations should be avoided. In particular, tablets containing AFA algae may contain toxins that damage the liver, kidneys and brain.