They provide about 1 gram of
omega-
3 fatty acids in about 3.5 ounces of
fish.
Fish oil supplements are usually made from mackerel, herring, tuna, halibut, salmon, cod liver, whale blubber, or seal blubber. Fish oil supplements often contain small amounts of vitamin E to prevent spoilage. They might also be combined with calcium, iron, or vitamins A, B1, B2, B3, C, or D.
Fish oil is used for a wide range of conditions.