Fish are packed with vitamins, minerals, proteins and omega-3 fatty acids. Salmon, mackerel, and herring are rich in omega-3 fats, which reduce inflammation, increase airflow and protect lungs from colds and respiratory infections. Shellfish such as oysters, lobsters, crabs, and clams are plentiful in selenium which help white blood cells to produce cytokines-proteins that help clear flu viruses out of the body. The American Heart Foundation suggests people to eat fish at least twice per week to protect their heart. Fish can also boost memory, combat cancer; support immune system and promote younger looking skin.