Omega-3 Source is a term used to describe foods that are rich in omega-3 fatty acids, which are essential for human health. COD, TUNA, and ROE are all sources of omega-3 fatty acids. COD is a type of fish found in the Atlantic and Pacific oceans, while TUNA is a saltwater fish found in tropical and subtropical waters. ROE is the eggs of fish, which can be eaten raw or cooked. All three of these foods are excellent sources of omega-3 fatty acids.