Vitamins in Seaweed

Seaweed is a nutrient-rich food that provides iodine, protein, iron, magnesium, potassium and phosphorus. It also provides a variety of vitamins. Types of seaweed featured in some Japanese soups include wakame and kelp, while dried nori or laver are eaten as a snack food. The various types of seaweed have similar nutrient compositions.

Vitamin A for Eye Health

A 1-cup serving of raw nori seaweed provides 4,161 international units of vitamin A, or 83 percent of the daily value for vitamin A. Vitamin A is essential for preventing night blindness and maintaining a strong immune system, according to the Linus Pauling Institute. It also allows your body to use iron properly to produce healthy red blood cells. Seaweed provides vitamin A is in the form of beta-carotene, which is an antioxidant.

Joint Health with Vitamin C

Each cup of raw nori seaweed supplies 31 milligrams of vitamin C, or 52 percent of the daily value for vitamin C. Vitamin C is an antioxidant vitamin and a necessary nutrient for a strong immune system. It also allows your body to synthesize cartilage to maintain healthy joints, according to the Linus Pauling Institute. Vitamin C also helps your body absorb iron from plant-based sources, such as seaweed, beans and spinach.

Increase Folate Intake

Raw nori provides 117 micrograms of folate, or 29 percent of the daily value, in a 1-cup serving. Folate is a B vitamin that works closely with vitamin B-12 and vitamin B-6 to metabolize an amino acid called homocysteine, according to the Linus Pauling Institute. Folate deficiency and high levels of homocysteine in your blood are risk factors for heart disease. Folate also helps protect against neural tube birth defects.

Low-Calorie, Too

Seaweed is low-calorie, with only 28 calories in a 1-cup serving. This serving size provides 4.7 grams of protein, or 9 percent of the daily value for protein based on a 2,000-calorie diet. A cup of seaweed supplies 64 milligrams of eicosapentaenoic acid, or EPA, which is a heart-healthy omega-3 fatty acid. The exact nutrient value of seaweed depends on the type of seaweed you purchase. Choose unsalted varieties to limit your intake of sodium, which is a mineral that can raise blood pressure.