Some types of seaweed are more nutritious than most land vegetables. Seaweed is very high in calcium, iron, magnesium and manganese. In seaweed, you will also find antioxidants and anti-inflammatory properties. Seaweed is also high in iodine, which is a mineral used to create thyroid hormones. If you don’t enjoy the taste of seaweed, you can take it in pill form or powdered form to throw into a smoothie or shake.