Pet Nutrition 101: What to Feed Your Dog or Cat

Walk into any pet store and you will be confronted with an entire aisle of food options — grain-free, raw-coated, high-protein, veterinary prescription, organic, limited ingredient, freeze-dried, dehydrated, and everything in between. The marketing claims are bold, the packaging is beautiful, and the prices vary from a few dollars to what feels like a small mortgage.

It is enough to make any pet owner's head spin.

The truth is that pet nutrition does not need to be complicated. Dogs and cats have specific nutritional requirements that are well understood by veterinary science, and meeting those requirements comes down to understanding a few fundamental principles. This guide will walk you through everything you need to know — from macronutrients and label reading to portion control and life stage feeding — so you can make confident, informed decisions about what goes into your pet's bowl.

Understanding What Dogs and Cats Actually Need

Before comparing food types, it helps to understand the basic nutritional needs of dogs and cats. Despite living together for thousands of years, these two species have fundamentally different dietary requirements.

Dogs Are Omnivores

Dogs are classified as facultative carnivores, which means they are primarily meat-eaters but can digest and benefit from plant-based foods as well. A balanced canine diet includes:

• Protein (from animal sources like chicken, beef, lamb, or fish) — Builds and repairs muscle, supports the immune system.
• Fat — Provides energy, supports skin and coat health, aids in nutrient absorption.
• Carbohydrates — While not strictly essential, digestible carbs from rice, sweet potato, or oats provide energy and fibre.
• Vitamins and minerals — Including calcium, phosphorus, vitamin A, vitamin D, and B vitamins.
• Water — Often overlooked but absolutely critical. Fresh water should always be available.

Cats Are Obligate Carnivores

Cats have stricter nutritional requirements than dogs. They are obligate carnivores, meaning they must eat animal-based protein to survive and thrive. Key differences include:

• Higher protein requirements — Cats need roughly twice the protein of dogs, and it must come from animal sources.
• Taurine — An essential amino acid that cats cannot synthesise. Without it, they develop heart disease and blindness. All commercial cat foods include taurine, but homemade diets often fall short.
• Arachidonic acid — A fatty acid found only in animal tissue that cats cannot produce on their own.
• Vitamin A — Cats cannot convert beta-carotene (from plants) into vitamin A. They need preformed vitamin A from animal sources.
• Very low carbohydrate tolerance — Cats have minimal ability to process carbohydrates. High-carb diets can contribute to obesity and diabetes.

The bottom line: You cannot feed a cat like a small dog. Their nutritional needs are distinct, and food formulated for dogs should never be substituted for cats.

Kibble (Dry Food): The Staple Diet

Kibble is the most popular pet food format worldwide, and for good reason. It is convenient, shelf-stable, affordable, and — when chosen well — nutritionally complete.

Pros of Kibble

• Convenience. Easy to store, measure, and serve. No refrigeration needed.
• Cost-effective. Generally the least expensive complete diet on a per-meal basis.
• Dental benefits. The crunching action can help reduce plaque buildup, though this varies by kibble size and hardness.
• Long shelf life. An unopened bag can last months. Once opened, kibble stays fresh for four to six weeks if stored properly in an airtight container.

Cons of Kibble

• Lower moisture content. Kibble contains only about 10 percent moisture, compared to 75 to 80 percent in wet food. This can be a concern for cats, who naturally have a low thirst drive and are prone to urinary issues.
• Processing. Kibble is made through extrusion, a high-heat process that can degrade some nutrients (which are then added back synthetically).
• Palatability. Some picky eaters, especially cats, find kibble less appealing than wet or raw food.
• Filler ingredients. Lower-quality kibbles may contain excessive corn, wheat, or soy as cheap fillers.

How to Read a Kibble Label

The ingredient list on pet food is ordered by weight before processing. Here is what to look for:

1. Named animal protein first. "Chicken" or "salmon" rather than "meat" or "animal derivatives." Named proteins are more transparent and generally higher quality.
2. Protein meal is acceptable. "Chicken meal" is simply chicken that has been dehydrated and ground. It is actually more protein-dense per gram than fresh chicken (which is 70 percent water).
3. Avoid vague ingredients. "Animal by-products," "meat and bone meal," or "cereals" without specification are signs of lower quality.
4. Check the guaranteed analysis. This tells you the minimum protein and fat percentages, and maximum fibre and moisture. For dogs, look for at least 22 to 26 percent protein and 12 to 16 percent fat. For cats, aim for 30 percent protein or higher.
5. Look for AAFCO or FEDIAF statements. These indicate the food has been formulated to meet established nutritional standards for a specific life stage (growth, adult maintenance, or all life stages).

Wet Food: More Moisture, More Flavour

Wet food — canned, pouched, or in trays — is typically more palatable and moisture-rich than kibble. Many pet owners use it as a supplement to kibble or as a primary diet.

Pros of Wet Food

• High moisture content. At 75 to 80 percent water, wet food helps keep pets hydrated. This is particularly important for cats, who are prone to kidney disease and urinary tract infections.
• Palatability. Most pets find wet food more appealing than kibble. It can be a lifesaver for picky eaters or seniors with reduced appetite.
• Easier to eat. Beneficial for pets with dental problems, missing teeth, or jaw issues.
• Higher protein, lower carbs. Wet foods often contain more animal protein and fewer fillers than comparable kibbles.

Cons of Wet Food

• Cost. Significantly more expensive per meal than kibble.
• Spoilage. Once opened, wet food must be refrigerated and used within two to three days.
• Dental concerns. Wet food does not provide the mechanical cleaning action of kibble, so dental care (brushing, dental treats) becomes more important.
• Less convenient. Heavier, takes up more space, and creates more waste (cans, pouches).

A Practical Approach: Mixed Feeding

Many veterinarians and nutritionists recommend a combination of kibble and wet food. This approach gives you the convenience and cost savings of kibble with the hydration and palatability benefits of wet food. A common ratio is 70 percent kibble and 30 percent wet food by caloric value.

Raw Feeding: The Controversial Choice

Raw feeding — giving your pet uncooked meat, bones, and organs — has grown enormously in popularity over the past decade. Advocates claim it mirrors what dogs and cats would eat in the wild, leading to shinier coats, healthier teeth, better digestion, and more energy. Critics, including many veterinary organisations, warn about bacterial contamination and nutritional imbalances.

What Is a Raw Diet?

The most common raw feeding model is BARF (Biologically Appropriate Raw Food), which typically includes:

• Raw muscle meat (chicken, beef, turkey, rabbit)
• Raw meaty bones (chicken necks, wings, lamb ribs)
• Organ meats (liver, kidney, heart — usually 10 to 15 percent of the diet)
• Vegetables and fruits (blended or pureed, around 10 percent for dogs; minimal for cats)
• Supplements (fish oil, kelp, vitamin E, depending on the formulation)

Commercial raw diets are also available — typically frozen or freeze-dried — and are formulated to be nutritionally complete. These are significantly safer and more convenient than DIY raw feeding.

Pros of Raw Feeding

• Improved coat quality. Many raw-fed pets develop noticeably shinier, softer coats.
• Dental health. Chewing raw meaty bones can help keep teeth clean.
• Smaller, firmer stools. Raw-fed pets typically produce less waste.
• No artificial preservatives or fillers.

Cons and Risks of Raw Feeding

• Bacterial contamination. Raw meat can carry Salmonella, E. coli, and Listeria, posing risks to both pets and human household members, especially children, elderly people, and immunocompromised individuals.
• Nutritional imbalance. DIY raw diets are frequently deficient in calcium, phosphorus, or essential vitamins unless carefully formulated by a veterinary nutritionist.
• Bone hazards. Cooked bones splinter and are dangerous, and even raw bones can cause tooth fractures or gastrointestinal blockages.
• Cost and inconvenience. Raw diets are expensive, require freezer space, and demand strict hygiene protocols.
• Not recommended by most veterinary bodies. The AVMA, BVA, and WSAVA all caution against raw diets due to contamination risks.

Our Take

If you are drawn to raw feeding, commercial frozen or freeze-dried raw diets from reputable brands are the safest option. If you choose to prepare raw food at home, work with a qualified veterinary nutritionist to ensure the diet is balanced. Never feed raw food to puppies, kittens, or immunocompromised animals without veterinary guidance.

The Grain-Free Controversy

Grain-free pet foods became wildly popular in the 2010s, driven by the assumption that grains are "unnatural" for dogs and cats. But the science tells a more nuanced story.

What Happened

In 2018, the US FDA began investigating a potential link between grain-free diets and dilated cardiomyopathy (DCM), a serious heart condition, in dogs. The concern was not about grains themselves but about what replaced them: legumes (peas, lentils, chickpeas) and potatoes, which often constitute a high percentage of grain-free formulas.

What We Know Now

The investigation is ongoing, but current evidence suggests:

• Most dogs tolerate grains well. Unless your dog has a diagnosed grain allergy (which is rare — only about 10 percent of food allergies in dogs involve grains), there is no reason to avoid them.
• Legume-heavy diets may be problematic. The high proportion of peas and lentils in some grain-free foods may interfere with taurine absorption or metabolism.
• Grain-free does not mean low-carb. Many grain-free foods simply substitute grain carbs with legume or potato carbs.

The Recommendation

Do not choose grain-free food unless your veterinarian has specifically recommended it for a diagnosed condition. For most dogs and cats, a well-formulated food containing rice, oats, or barley is perfectly healthy and may be safer than a grain-free alternative.

Feeding by Life Stage

The nutritional needs of pets change significantly throughout their lives. Feeding the right diet for each stage is one of the most important things you can do for your pet's long-term health.

Puppies and Kittens (0 to 12 Months)

Growing animals need more of everything — more protein, more fat, more calories, and more frequent meals.

• Puppies: Feed a food labelled for "growth" or "all life stages." Large-breed puppies need specifically formulated large-breed puppy food, which controls calcium and phosphorus levels to support healthy bone development.
• Kittens: Feed a kitten-formulated food with high protein (at least 30 percent) and adequate taurine.
• Feeding frequency: Three to four meals per day for puppies and kittens under six months, transitioning to two meals per day by 12 months.

Adult Dogs and Cats (1 to 7 Years)

• Maintenance diet. An adult-formulated food that meets AAFCO or FEDIAF standards for adult maintenance.
• Feeding frequency: Most adult dogs and cats do well on two meals per day. Some cats prefer grazing (free-feeding), but this increases the risk of overeating and obesity.
• Monitor weight. Adjust portions based on activity level, body condition, and any weight changes.

Senior Dogs and Cats (7+ Years)

Older pets have different needs:

• Lower calories. Senior pets are typically less active and prone to weight gain.
• Higher protein. Contrary to old advice, senior pets benefit from maintained or even increased protein to preserve muscle mass.
• Joint support. Look for foods with glucosamine, chondroitin, or omega-3 fatty acids.
• Kidney considerations (cats). Senior cats are at high risk for kidney disease. Your vet may recommend a kidney-support diet with controlled phosphorus levels.
• Feeding frequency: Two meals per day, or smaller, more frequent meals if appetite is reduced.

Portion Control and Obesity

Pet obesity is an epidemic. Studies consistently show that 50 to 60 percent of dogs and cats in developed countries are overweight or obese. The consequences are serious: shortened lifespan, joint problems, diabetes, heart disease, and reduced quality of life.

How to Determine the Right Portion

1. Start with the feeding guide on the package. These are rough guidelines based on weight, so treat them as a starting point, not gospel.
2. Weigh the food. Use a kitchen scale rather than a measuring cup. Cups are inaccurate — studies have shown that people consistently overpour by 10 to 50 percent when using cups.
3. Assess body condition. You should be able to feel your pet's ribs without pressing hard, and they should have a visible waist when viewed from above. If you cannot feel ribs, your pet is overweight.
4. Adjust every two to four weeks. Monitor weight and body condition and adjust portions up or down accordingly.
5. Account for treats. Treats should make up no more than 10 percent of daily caloric intake. If you use training treats, reduce the main meal portion accordingly.

Common Mistakes

• Guessing portions. "A scoop" or "a handful" is not a measurement.
• Leaving food out all day. Free-feeding makes it impossible to monitor intake and encourages overeating.
• Ignoring treats. A few dental chews and training treats can add hundreds of calories per day.
• Feeding human food. Table scraps often contain excessive fat, salt, and sugar. Some human foods are also toxic to pets.

Common Food Allergens

True food allergies in pets are less common than many people believe — they account for roughly 10 to 15 percent of all allergic skin disease in dogs. Environmental allergies (pollen, dust mites) are far more prevalent.

When food allergies do occur, the most common culprits are:

In Dogs

1. Beef
2. Dairy
3. Chicken
4. Wheat
5. Soy

In Cats

1. Beef
2. Fish
3. Dairy
4. Chicken

How Food Allergies Are Diagnosed

The only reliable way to diagnose a food allergy is an elimination diet trial supervised by your veterinarian. This involves feeding a novel protein (one your pet has never eaten) or a hydrolysed protein diet for eight to twelve weeks, then systematically reintroducing ingredients to identify the trigger.

Blood tests and saliva tests for food allergies are widely marketed but have been shown to be unreliable. Do not waste your money on them.

Toxic Foods to Avoid

Some human foods are genuinely dangerous for dogs and cats. Make sure everyone in your household — and your pet sitter — knows to avoid these:

Toxic for Dogs and Cats

• Chocolate — Contains theobromine. Dark chocolate is most dangerous.
• Onions and garlic — Damage red blood cells. Even small amounts are harmful to cats.
• Grapes and raisins — Can cause acute kidney failure in dogs. The exact toxic compound is still unknown.
• Xylitol (birch sugar) — Found in sugar-free gum, some peanut butters, and baked goods. Causes rapid insulin release and liver failure in dogs.
• Macadamia nuts — Cause weakness, vomiting, and hyperthermia in dogs.
• Alcohol — Even small amounts are dangerous.
• Cooked bones — Splinter and can puncture the digestive tract.
• Caffeine — Coffee, tea, and energy drinks are all dangerous.

Safe Human Foods (in Moderation)

• Carrots, green beans, pumpkin (plain, cooked)
• Blueberries, watermelon (seedless), apple slices (no seeds)
• Plain cooked chicken, turkey, or fish
• Plain rice or pasta (as a bland diet for upset stomachs)

Communicating Feeding Instructions to Your Pet Sitter

When you leave your pet with a sitter — whether for a day visit or a week-long stay — clear feeding instructions are essential. Miscommunication about diet is one of the most common sources of pet sitting problems.

Here is what to include in your feeding notes:

Essential Information

1. Brand and type of food. Be specific: "Royal Canin Medium Adult kibble" is better than "the brown bag in the pantry."
2. Exact portions. Use weight (grams) or precise measurements. Leave a measuring scoop if helpful.
3. Feeding times. "7am and 6pm" is clearer than "morning and evening."
4. Where the food is stored. And how much you are leaving — if it might run out, tell the sitter where to buy more.
5. Fresh water. Remind the sitter to refresh water daily (or more frequently in warm weather).

Important Details

6. Treats allowed. What type, how many, and when. Include any training treats.
7. Allergies or dietary restrictions. List any foods your pet cannot have.
8. Medication mixed with food. If your pet takes medication in their food, explain the process clearly.
9. Behavioural notes. "She eats slowly — do not take the bowl away until she is finished" or "He guards his food — give him space while eating."

When you book through The Pet Sitter, you can include detailed feeding instructions in your booking notes. Take the time to be thorough — your sitter will appreciate it, and your pet will be better off.

Frequently Asked Questions

Is wet food better than kibble?

Neither is inherently better — they each have advantages. Wet food provides more moisture and is often more palatable, while kibble is more convenient and cost-effective. Many veterinarians recommend a combination of both. The most important thing is choosing a product that meets established nutritional standards (look for AAFCO or FEDIAF compliance) and suits your pet's individual needs.

Should I feed my cat a raw diet?

Raw feeding can work for cats when done correctly, as cats are obligate carnivores with high protein needs. However, the risks of bacterial contamination and nutritional imbalance are real. If you want to try raw, use a commercially prepared, nutritionally complete raw food rather than DIY. Always discuss dietary changes with your veterinarian first.

How do I know if my pet is overweight?

Perform a simple body condition assessment: run your hands along your pet's sides. You should be able to feel the ribs without pressing hard. When viewed from above, your pet should have a visible waist behind the ribs. From the side, the abdomen should tuck up slightly. If the ribs are buried under a layer of fat and there is no visible waist, your pet is likely overweight. Your veterinarian can confirm and recommend a weight management plan.

Can I switch my pet's food suddenly?

Abrupt food changes often cause digestive upset — vomiting, diarrhoea, or refusal to eat. The recommended approach is a gradual transition over seven to ten days: start with 25 percent new food mixed with 75 percent old food, and slowly increase the proportion of new food each day. If your pet has a sensitive stomach, extend the transition to two weeks.

Final Thoughts

Pet nutrition does not have to be overwhelming. The fundamentals are straightforward: choose a high-quality food formulated for your pet's species and life stage, feed appropriate portions, provide fresh water, and monitor body condition. Skip the marketing hype, read the label, and consult your veterinarian if you have questions.

And when you travel, make sure your pet sitter knows exactly what, when, and how much to feed. A well-fed pet is a happy pet — and a happy pet makes for a stress-free trip.

Looking for a pet sitter who will follow your feeding routine to the letter? Find trusted sitters near you on The Pet Sitter.