Some scientific studies indicate that green laver and purple laver, also called “Nori“, contain substantial amounts of biologically active vitamin B-12. Nori is available in many supermarkets and grocery stores. It is edible seaweed formed into thin sheets, and often used in making sushi.
The second of the above studies indicates that sufficient vitamin B-12 can be obtained from 1 gram of Nori per day.
B-12 is also found in Duckweed (“water lentils”)