Seaweed contains a variety of vitamins including vitamin A, vitamin C and nearly one-fifth of the daily recommended value of vitamin K. Seaweed also provides vitamin B group nutrients, such as pantothenic acid and riboflavin, that are needed to promote energy production and boost metabolism.
Seaweed is full of phytonutrients, such as sulfated polysaccharides, that have cardiovascular health benefits. It also contains bioactive peptides, which help lower blood pressure and improve cardiovascular health. Other essential nutrients in seaweed include copper, zinc, folic acid, magnesium and iron.
There are only 8 calories in a 1/4 cup serving of seaweed. Seaweed is rich in potassium; a 10-gram serving of red seaweed contains 34 times the amount of potassium as the same serving size of banana. Seaweed is also an excellent source of iodine, which helps regulate the thyroid and prevent hyperthyroidism. It is high in fiber, which improves digestion and regulates blood sugar.
The high concentration of certain minerals in seaweed is sometimes an issue because it means consuming an excess of those minerals. This poses an issue for people with kidney problems, thyroid problems or other medical issues that limit mineral consumption. Nori is a type of seaweed that contains omega-3 fatty acids and lower amounts of iodine than most other seaweed varieties, which makes nori seaweed safe to consume several times per week.