The invention relates to a brown algae extract containing less than 50 ppm of iodine and between 5 and 15%, and preferably between 8 and 10%, of polyphenols, said percentage of polyphenols being expressed as a chlorogenic acid equivalent in relation to the dry weight of the extract, the invention also relating to an oral absorption composition comprising such an extract, and to a method for preparing the extract according to the invention.
