Monday, June 9, 2014

What is the best cat food to feed my cat?



Cat eating kibbles | Exclusively Cats Veterinary Hospital, Waterford, MI
Nutrition is based on life stages and overall health. You would not feed the same thing to a kitten that you would feed to a 6 year old cat or a 14 year old cat, and you would not feed the same thing to a healthy cat that you would feed to a diabetic cat, or a cat with kidney disease. 

Pet nutrition has become a very hot topic in the last several years, with good reason. There have been a great number of recalls, and a number of revolutions in the way we think about feeding pets (Canned food vs. dry food, raw food vs. traditional diets, carbohydrates vs. proteins...). If you asked 7 different pet owners or veterinarians what food you should feed your pet, you would probably get 7 different answers.

In the wild, a cat would eat a variety of prey animals – primarily mice and other rodents, insects, birds and frogs (rarely fish!). The average mouse is about 75% water, and provides about 3-5% carbohydrates. No matter what your cat eats, it should not eat a food that contains more than 10% carbohydrates.
Shutterstock image of a cat eating a big chunk of raw meat | Exclusively Cats Veterinary Hospital, Waterford, MI

Let’s say we are talking about a normal, 5 year old, healthy cat. Because most foods have the statement “formulated to meet the nutritional levels established by AAFCO Cat Food nutrient profiles for all life stages” on the label – most would be an appropriate option for basic nutrition. Your cat will not suffer any nutrient deficiencies while eating a food with this label.

Let's compare two brands of food, just to see how complex it can be to determine which is better. A can of Instinct turkey flavored food costs about $1.25 per 3oz can. Fancy Feast turkey and giblets costs about $0.60 per 3 oz can.  Common sense would suggest that if a food costs more, it must be higher quality. Let's take a closer look.

Since canned food is mostly water, meat also contains a large amount of water, and the amount of water may very between canned foods, you have to do a little math to figure out what nutrients the actual solid part of the food contains. This also allows you to compare between canned foods, or compare a wet food to a dry food. If you take a few minutes to calculate the dry matter carbohydrate content of the food, you will see that the Instinct food has 18% carbohydrates on a dry matter basis (DMB)!! That’s pretty high for a cat. Fancy Feast has a carbohydrate content of 6.8%. Instinct is also 10% lower in protein and 8% higher in fat. It also has about twice the calories of the Fancy Feast. A cat with weight issues might not want to eat this food, no matter how much kelp it has in it…and speaking of kelp, why would your cat need kelp in his diet? Kelp may have some great nutritional benefits on a chemical level, but cats are descended from desert animals - their digestive tract is not designed to digest it. 

Cat digestive tracts are much simpler than a human’s or a dog’s. The way they digest foods takes a lot of shortcuts – skipping important steps that relate to carbohydrates, vegetables, fruits – things that are not part of their natural diet. Even though apples, blueberries, pumpkins and flax have great nutritional benefits – if they are in whole-food form, their nutritional benefits may stay locked away from use if eaten by a cat. If given in supplement form (raw vitamins, omega fatty acids, etc.), they are likely of much more use.
Cat eating a carrot | Exclusively Cats Veterinary Hospital, Waterford, MI

In fact, while artichokes, pumpkin and cranberries sound yummy to us, cats are obligate carnivores – that means that they HAVE to eat meat. Meat, meat and (almost) only meat! In reality, most cats would get vegetables/grains/fruits only if they ate the pre-digested contents of their prey’s stomach. A cat could NEVER be a vegetarian and be healthy. They get taurine from muscle meat – it is an amino acid that dogs and people can make in their bodies. Cats can’t, so they need it in their food, or they suffer damage to their hearts and eyes. Dogs might raid a trash can and eat your leftovers. If a cat was REALLY REALLY hungry, he might, but he’s not looking for the carrots or the chocolate cake – he is looking for that turkey gristle, or the fish bones. 

Cats rarely will choose to eat vegetables. They also tend to hate citrus. But even if they eat it, it doesn’t mean they can digest it. Most cats will drink milk or eat other dairy products, but the majority of cats are also lactose intolerant. It means they can’t digest milk proteins. Cats will also eat ear plugs, shoelaces, plastic bags, hair bands, rubber bands, ribbon…Just because they eat it, doesn’t mean they can digest it! So, just because a cat is eating kelp and broccoli and loving it doesn’t mean that its body can break down the food and use it for nutrition. 

Similarly, Instinct contains tomatoes, which are members of the Solanaceae family of plants which
Cats are obligate carnivores | Exclusively Cats Veterinary Hospital, Waterford, MI
includes the Deadly Nightshade. Tomatoes contain a bitter, poisonous alkaloid called glycoalkaloid solanine that can cause violent lower gastrointestinal symptoms. Generally cats aren't attracted to tomatoes, but there have been reports of a single cherry tomato causing a near-fatal reaction. Green tomatoes and the leaves and stems are all toxic. This toxin is destroyed by cooking, so I would have to assume that the tomato in the Instinct diet is cooked, or in such small quantities that it is non-toxic, but why even put a toxic veggie into the food? This is one reason that it is a good idea to use foods whose companies have done feeding trials – they can tell you in detail how the food affects a cat – what its urine concentration or pH is, blood levels of vitamins (so you know they are really getting them), etc.

The ingredients are listed on the label in the order of greatest content by weight to least content. Allowing for the fact that the order of ingredients does not tell us quantity, we do know that Instinct says that it is 95% duck and turkey liver. We don't know whether Fancy Feast is 95% turkey and liver or not, but we do know that they are the two ingredients that make up most of the food by weight. The first 5 ingredients on the Fancy Feast are meat-related products. Only the first two on the Instinct label are meat related. Then comes water and then flax (which a cat may or may not be able to digest). Both have all the necessary vitamins and minerals. Instinct has clay in it? The Montmorrilonite clay may have benefits for people, but I highly doubt that any research has been done on cats and the benefits of ingesting clay. What’s good for people is not necessarily good for cats. Many people love to eat garlic and chocolate (not at the same time, of course!). But both garlic and chocolate are toxic to cats. Besides, a cat likely gets plenty of clay in his diet from cleaning his paws after using the litterbox.

Don't believe what you read about "meat by-products" either. Most Internet sites will have you believe that "meat by-products" are beaks and toenails, roadkill, euthanized shelter animals and intestinal contents, but in reality they are organ meats: lungs, spleen, kidneys, brain, liver, blood, bone, and cleaned stomach and intestines. The FDA has tested multiple brands of pet foods and has found no sign of dog or cat DNA in any of them.
A cat's diet is not well-rounded, it's primarily meat | Exclusively Cats Veterinary Hospital, Waterford, MI
Most of the ingredients of this diet are grains and vegetables, not meat

So, long story short – if we were going to pick one of these two foods as the best food to feed a young, healthy cat, we would pick the Fancy Feast! It has a better protein/carb/fat ratio, more water, fewer questionably digestible ingredients (which means potentially more nutrient bioavailability). We are not suggesting that Fancy Feast is the best food on the market, today, but that it is a viable and reasonable choice to feed your cat, and that the more thought and consideration you put into your cat food choice, the more likely you are to pick a decent food.

Your individual cat may have specific dietary requirements or sensitivities that mean that Fancy Feast is not the best choice, or you may pick a food that you have examined and determined to be a great food for your cat, but he or she just won't eat it. There is no perfect food for all cats. We hope that some of the issues that have come about due to recalls and consumer complaints will help change pet foods for the better. It is an ever-evolving field, and with informed consumers, things can only get better!

Further reading:
A long and short article about the benefits of canned foods.