When I was young, my parents used to buy a packet of assorted seaweed, and brew it in a sweet soup. We ate it as a snack at 3 pm. It is supposed to cleanse your blood,and I can attribute it to having very little pimples.
These days, you can buy processed seaweed salad. This packet is not really processed. You have to soak in water before you add the sauces. There are those from China where you can eat straightaway.
New Zealand waters are rich in sea weed.