Seaweed as food: survey of the UK market and appraisal of opportunities and risks in the context of iodine nutrition

Purpose Seaweeds are gaining broader interest in Western societies through their use in product development and the health-food industry. High nutritional value, low carbon footprint and sustainability are key drivers for seaweed uptake in Europe; yet high iodine intake from seaweed remains a concern. This study seeks to identify seaweed food products available on the UK retail market between 2018 and 2021 and assess their safety in the context of iodine exposure.Design/methodology/approach Here, a market survey (n = 37–40 retailers) was conducted in three annual waves to evaluate seaweed food product availability in the UK. The iodine dose of products was estimated based on a comprehensive literature review of seaweed iodine content.Findings This study shows a young, dynamic market with 2.3-fold increase in seaweed food product availability since the last available published data (2015). Specific iodine content labelling remains uncommon, and median iodine doses in a single serving of food exceeded 400 µg in all years. Some products, especially seaweed supplements, provide iodine doses above the tolerable upper limit and upper level of tolerance.Originality/value This study presents the most contemporary and comprehensive overview of the market for seaweed food products in the UK. With increasing popularisation of seaweed as a food, this study highlights the need for improved dialogue amongst producers, retailers, legislators and public health specialists to address the risk of iodine excess, and the concurrent scope for processing methods to reduce the iodine content in seaweeds.