The Seaweed Research Group at the University of Gothenburg Tjärnö Marine Lab are one of the foremost units looking at how seaweed can be a big part of a sustainable future. A number of cultures have a history of including seaweed in their diet, but ramping seaweed as a food source up to impactful levels and in a sustainable way is a whole different challenge. In addition, there is the potential for seaweeds to fulfil other roles such as animal feed, cosmetics, coastal protection, biofuel and more.
They have a good video on seaweed as food on their website:
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