Kelp tablets are a convenientway to include some seaweed in the diet. Because of their high iodine content, some herbalists prescribe them for mild thyroid disorders. The freshwater algae supplements spirulina and chlorella are increasingly popular. They contain all the nutrients that you would expect to find in green vegetables, including beta carotene, vitamin C, calcium and iron. They also cotain protein and vitamin B12. It is claimed that spirulina is a good source of the essential fatty acid, gamma linolenic acid (GLA). I find that every few months I feeel the need for kelp. Awareness of the body and the body’s needs is an essential part of yoga practice.