It’s no surprise to learn that cats love fish – it is so common it’s stereotypical. Tuna (along with other fish) contain omega-3 fatty acids which has been known as an anti-inflammatory. Fish is also a lean protein that is excellent for building strong muscles. In addition, the natural oils found in fish helps to keep a cat’s coat shining and its skin healthy. However, there is a downside to canned fish. Some of these products can be high in mercury, so its best to only let kitty munch on these morsels in moderation.