All types of shellfish are rich in iron. But mussels, oysters, and clams are especially great sources of this essential minerals. A portion of claims would provide up to 17 percent of the daily recommended intake. The iron level in clams can vary a lot, depending on the variety. Heme iron is the form of iron found in shellfish. Compared to non-hemeiron form in plant-based foods, it can be absorbed more easily by the body. Other important nutrients in shellfish include vitamin B12, vitamin C, and protein. Research has shown that this food may help increase the level of HDL cholesterol, which benefits heart health. While there are certain worries about toxins and mercury in wild-caught shellfish, the advantages far outweigh the disadvantages.