If your cat loves fish, he has lots of company! However, it’s really not a good idea to feed fish to your cat; and here’s why:
The primary fish used in cat food are salmon, tuna, and tilefish (ocean whitefish). Let’s look at each of these.
Salmon: The vast majority of salmon today comes from farm-raised fish. In this form of factory farming, millions of these unfortunate animals are kept in huge, overcrowded pens in polluted coastal waters. They’re fed antifungals and antibiotics to limit the spread of disease, and dyes to make their flesh salmon-colored (otherwise it would be gray). Common water pollutants, such as PCBs, pesticides, and other chemicals, are found in farmed salmon at ten times the amount found in wild fish. These contaminants will be present in any product made with farmed fish, including pet food.
It has recently been revealed that krill, tiny shrimp that are the natural diet of many whales and other marine animals, are being netted in vast hauls, and processed into food for these “franken-salmon,” for their protein as well as their red color. The issues with krill are explained below.
Tuna: It’s the fish that’s most “addictive” to cats. They love it so much that they may stage a hunger strike by refusing their regular food until they get it!
Tuna and other predatory fish are at the top of the food chain. This means that they may accumulate high levels of heavy metals (including mercury) as well as PCBs, pesticides, and other toxins, by eating smaller fish. The older the fish, the more contamination.
Tilefish: (listed on pet food labels as “ocean whitefish”) are among the worst contaminated, along with king mackerel, shark, and swordfish. These fish are so toxic that the FDA advises women of child-bearing age and children to avoid them entirely; and the FDA recommends only one serving of albacore tuna per week due to its high mercury levels.
The fish used in canned pet foods is typically whole fish, or leftovers from processing whole fish, deemed unsuitable for human consumption; this includes guts, feces, and bones, which are high in phosphorus—a problem for cats with kidney disease. On the other end of the urinary tract, many sensitive cats develop cystitis (bladder inflammation) and even urinary blockages if they eat any kind of fish at all. Fish and fish meal are both problematic.
A small amount of fish, such as wild caught sardines, used as a flavoring in a properly balanced, fresh meat-based diet, is not a problem. But fish should not be the main course for the cat’s diet.
But what about Omega 3 fatty acids? Aren’t fish and fish oils the best sources of these essential fats for our pets? Indeed, daily Omega- 3 supplementation from a marine source is extremely important for our cats as well as for us. Among many other benefits, Omega 3s fight inflammation, which affects our cats as much as it does us.