Mussels have the most impressive nutritional profile of all shellfish. They contain high levels of highly desirable long chain fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). These fats have many beneficial effects, including improving brain function and reducing inflammatory conditions, such as arthritis. Mussels are also a brilliant source of vitamins. Plus they give you a shot of important minerals, such as zinc, which helps build immunity. Mussels even contain levels of iron and folic acid to rival red meats.