Seaweed has long been touted as a superfood, and now sea moss, sometimes called Irish sea moss or Irish moss, has entered the wellness lexicon. Proponents have claimed that sea moss does everything from boost immunity and soothe digestion to strengthen joints and improve skin health. Sea moss is a type of algae, which has been part of the human diet for thousands of years. In addition to being consumed historically in places like the Caribbean and Ireland, sea moss has been used medicinally in other cultures for decades, to treat conditions ranging coughs and infections.