Cats are carnivores and require a high amount of protein in their diet. In fact, kittens need about 50% more protein in their diet than puppies, and adult cats need 200% more protein in their diet than adult dogs.
Cats require a three essential amino acids: taurine, arginine, and methionine. Taurine is required to have a healthy heart, good vision, and functioning reproductive systems. Arginine is required for a cat’s liver to function properly and filter out harmful byproducts from their body. In fact, eating a single meal deficient in arginine can make a cat ill from ammonia toxicity. Methionine plays a role in many different proteins in a cat’s body and deficiencies can affect a cat’s coat, skin, eyes, and heart health. All of these amino acid are only found in meat, so all cats need meat-based diets to maintain their health.
That being said, cats do have enzymes in their digestive tract that can digest carbohydrates, so the starches found in many cat foods can be digested for energy. For growing and active animals, this can be an effective source of energy. But these starches should only make up a small portion of the cat’s food, about 35% max.
For a cat, vegetarian diets are absolutely out of the question. Not even nutritional supplements can allow a cat to eat vegetarian or vegan, because some of their essential nutrients are only obtainable from animal products. For example, sources of Vitamin A can come from plants, as carotene, or from animal livers, as retinyl palmitate. Cats lack the enzymes to convert carotene to Vitamin A–they can only convert retinyl palmitate from animal livers to Vitamin A. So, they necessarily need to consume animal products to survive.
Finally, we’ll discuss the most important nutrient for cats: water. Keeping your cat well-hydrated is vital in preventing diseases associated with the urinary tract. Wild cats receive most of their hydration from the prey they eat, so sometimes it can be a little tricky to keep your house cat hydrated. Here are a few tips:
- Cats with sensitive whiskers might prefer to drink from a wide, shallow bowl.
- Some cats prefer a source of running water, so investing in a cat fountain might encourage your cat to drink more water.
- Change your cat’s water supply frequently, wiping away any residue on the bowl.
- Aim to keep your cat’s bowl as clean as your own glassware, even occasionally running it through the dishwasher.
- Some cats will not drink water that is placed next to their food source or litter box, so try moving their water bowl to another area.
- Milk is not a replacement for water, and can actually give your cat serious digestive issues.
- Wet food can help supplement your cat’s hydration, but only giving your cat wet food can lead to dental health issues.
Dogs are omnivores, which may come as a surprise to some dog owners. Although wolves are primarily carnivores, during the process of domestication, dogs gained the ability to effectively digest starches. In fact, dogs have about four to thirty copies of a gene that produces an enzyme for digesting starches in their bodies. In contrast, wolves only have two copies.
This provides evidence that a raw meat diet is not the best choice for our canine companions, because their bodies have adapted to digesting starches and using them for energy. In fact, a raw meat diet can have harmful effects, because it contains too much protein, not enough carbohydrates, and can be difficult on a dog’s kidneys. It’s interesting to note that even wolves will graze on grasses and eat the stomach contents of herbivorous prey to supplement their primarily meat-based diet with carbohydrates.
Think of it this way: if a raw meat diet isn’t nutritionally complete enough for a wolf, it will definitely pose problems for a dog, whose species has over many generations adapted to eat grains and vegetables while coexisting with human society.
On the other hand, dogs do require some proteins that are only available in animal products, so switching your dog to a vegetarian diet can pose issues as well. Although it is possible for dogs to survive on both of these specialized diets with the right supplementation and guidance from a veterinary nutritionist, a dog will only thrive when it eats as an omnivore, because its body is adapted to an omnivorous diet.
Let’s not forget the most important nutrient for dogs: water! Make sure that your dog always has access to clean, fresh water, especially after work or exercise. Change the water in your dog’s bowl at least once a day and be sure to wipe away any build-up on the inside of the bowl when you do this. Aim to keep your dog’s water bowl as clean as your other glassware to keep your dog healthy and happy.