Home The Best Dog Food in 2021 The Essential Guide to Canine Nutrition

The Essential Guide to Canine Nutrition

If you buy through links in this article, we may earn a commission. This policy helps support the website's operation. Learn more.

While you can just take the recommendations of reviewers and manufacturer’s at face value, there’s a lot to be said for actually knowing about your dog’s nutritional requirements. Making your own, educated choices is one of the essential pieces of dog ownership, especially since so many people out there simply want to sell you something.

We’ve decided to put together an in-depth guide to nutrition for your dog, in order to allow you to come to the best conclusions rather than having to rely blindly on second-hand information.

Why Should You Learn Canine Nutrition?

We’re not saying that you need to learn a whole veterinary nutritionist degree’s worth of information, but the basic information is readily available and spending a little bit of time learning is a great investment for your pet’s health.

This will let you make sure that you know which food is best for your animal and will also help you to figure out if there needs to be a change in diet or supplementation over time.

There’s a whole host of reasons why you should spend a little bit of time making sure you know at least the basics of canine nutrition, but we think the following should convince most people with furry friends roaming about to spend some time learning:

  • Learning dog nutritional requirements is a great way to ensure your dog stays healthy throughout their lifespan.
  • Some ailments can be traced back to improper micronutrient levels and be easily fixed without an expensive veterinary visit.
  • If you do home cooked meals, it should be of special importance to you since many of the commonly held beliefs about dog’s diets are simply wrong.
  • Rest assured in the knowledge that you actually know what’s best for your dog by eliminating guesswork.
  • Even if you know human nutrition, dogs have a rather different metabolic cycle which makes it hard to extrapolate properly between what’s good for a human and what’s good for your dog.
  • It can be fun!

So, if any of the above reasons appeal to you then it’s time to get down to the brass tacks, pull on your learning cap, and find out something about the exciting world of canine nutrition.

The Big Differences in Metabolism

One of the main things that people make a mistake about when they’re looking into dog nutrition is assuming that things work directly across from their knowledge of human nutrition. Things don’t quite work that way.

Of course, some people swing to the other extreme and consider their dogs to be solely carnivorous. The truth of the matter is that few animals are true carnivores, or herbivores for that matter, and a dog can get seriously ill if it’s fed a 100% meat diet.

While some dogs do survive on this diet, it’s pretty much guaranteed that they’re getting other nutrient sources. Our canines are actually rather omnivorous. While a feral dog will likely have a higher portion of meat in their diet than a human, if they can get it, our pets have adapted to be able to eat just about anything.

The main difference from human nutrition is the lowered requirement for carbohydrate intake. While humans primarily utilize carbohydrates for endurance draining activities, dogs utilize proteins and fats at a much more efficient rate. In fact, the primary use for most dogs of carbohydrates is from fiber, which smooths the GI tract.

Dogs thus have a higher requirement for fat and proteins with a much lower carbohydrate requirement than their owners.

We’ll go over the differences in vitamins and minerals later in this article, just try not to skip too far ahead when we’re talking even if you think you already know what’s going on with your dog’s diet.

Macronutrients and Your Canine

Macronutrients are the bulk make up of food stuffs. If you remember your high school or middle school health classes, then you know the basic breakdown is as follows:

  • Carbohydrates
  • Fats
  • Protein

Each of these can be further broken down into separate categories, with some things being “good” or “bad” throughout.

Since macronutrients comprise the bulk of any given food, they’re responsible for determining most of a food’s utility.

Caloric Requirements for Dogs

The amount of each of these is used to calculate the calories contained within food:

  • Carbohydrates contain 4 calories/gram, with indigestible fiber usually being subtracted before calculations
  • Fats contain 9 calories/gram
  • Protein contains 4 calories/gram

If you keep the above in mind, you can easily calculate the amount of calories in a food which doesn’t have the amount labeled right on the package.

Dogs will have varying needs, depending on activity level, age, and breed. Making sure that you get them roughly the right amount of calories each day is one of the most important things you can do to help them maintain a healthy weight.

If nothing else, you should know your dog’s requirements. For the average dog, meaning a medium or large breed with an average activity level you’ll find that about 30 calories per pound is pretty much ideal.

Smaller breeds have quicker metabolisms, however, which means that they can take up to 40 calories per pound of body weight without pushing things too far.

So, for instance, a 90lb German Shepherd might need 2,700 calories through a day while a 15lb terrier might need as much as 600.

Of course, this is only for an average, adult dog.

When you’re calculating the range for puppies you’ll want to feed them about twice as much per pound of body weight than you would an adult dog. So a 10lb puppy should receive 60 calories per pound of body weight, or 600 calories.

Meanwhile, elderly dogs will have a caloric intake about 20% lower than an adult dog. If we take the German Shepherd from our above example, weighing in at 90lbs, you’ll calculate at 24 calories/pound or 2,160 calories for ideal weight.

Calculating calories in this way is going to give you the rough ballpark figure. Individual metabolism can make this vary by as much as 20% either way, and dogs partaking in more strenuous activities during the day like hiking can require up to 200% of their normal intake to maintain weight.

Monitoring your dog’s caloric intake is only part of the battle, however, monitoring the macronutrients as a whole is also imperative to ensuring your dog’s health.


Dogs, while not strict carnivores, have a pretty high protein requirement. Proteins are comprised of vital amino acids and there are quite a few which a dog can’t synthesize within their own body.

As a general rule, a dog’s diet should consist of at least 28% protein by weight, and in many cases, a dog will be better off with an increased amount. The “ancestral” diet is estimated to have been about 52% by weight, but that may be pushing it for a modern dog and somewhere from 35%-45% is probably ideal.

Keep in mind that nutrient ratios still aren’t an exact science.

Not all protein is equal for that matter, the digestibility of proteins varies based on the original sourcing of the ingredients. Egg whites, for instance, have a much higher digestibility of protein than corn for instance.

When you’re looking at the ingredients you can always assume that animal sources are much more useful for your canine than vegetable sources. We’ve compiled a table of the more common ingredients to let you see for yourself:


Food Digestibility
Egg Whites 100%
Muscle Meat 92%
Organ Meats 90%
Dairy 89%
Fish 75%
Soy 75%
Rice 72%
Oats 66%
Yeast 63%
Wheat 60%
Corn 54%


As you can see, the digestibility varies quite a bit but as a whole, you’ll be fine as long as the main part of the protein is coming from animal sources. Fish has a lower digestibility index, but it also contains some vital fats so don’t discount it as a good source of nutrients if you’re making homemade meals for your dog.

When you’re looking at a food, never take their word for it that it’s high protein. Take a look at the nutrients break down and the source which the protein is coming from in order to get the most accurate picture possible of what’s going on.

After all, a diet which is 25% crude protein but receives it all from wheat, isn’t actually going to be all that healthy.

Dogs can actually metabolize protein into glucose quite easily, which is why their carbohydrate intake is reduced so much from that of a human: it becomes a readily available source of energy for the canine.

Too much protein can cause roughly the same problems it does in humans, namely renal issues, but it doesn’t seem that dogs fare well with a reduced protein diet. As long as you keep things under 50% your average dog shouldn’t have any issues arising.


Canine nutrition requires a much higher portion of fats than most humans receive from their diet. While many humans restrict the fat in their diet, you definitely don’t want to do this to your pup. Unlike humans, your dog will actually metabolize about 90%-95% of their fat intake into energy.

Fats are both a readily available source of energy for a dog, it’s actually vital if they’re undertaking strenuous activities, and are required to keep their fur, skin, and other essentials healthy.

Omega-3 and Omega-6 fatty acids are some of the most important parts of your dog’s macronutrient intake and you should make sure that the ingredients in your foods contain a good portion of them.

The dietary fat which your canine takes in is super important, but too much of it can cause pancreatitis and, in extreme cases, cardiovascular problems. They should only make up about 25%-30% of your dog’s total caloric intake if you want to ensure that you’re in good hands.

Most commercial foods are quite a bit lower than this, of course.

The most important thing to remember about fats is simply that they make up for a huge amount of calories, double that of protein or carbohydrates, and your dog pretty much needs them in order to maintain their optimal health.


Carbs are the most controversial of the macronutrients when it comes to dogs. It would seem no two canine nutritionists can agree on how much a dog needs.

The thing is, most food items which are good carb sources are also excellent sources of micronutrients that can’t be received simply from meat or fish. These include both minerals and vitamins.

Fiber is also included with carbohydrates, while indigestible it actually helps smooth out the gastrointestinal process quite a bit.

This means that it’s important to check up on where the carbohydrates in your dog’s food are coming from. Grains are an inferior source, as a general rule, especially when you compare them to vegetables and fruits.

The hot contesting of the amount of carbohydrates contained within a dog’s diet is why you don’t generally see the amount on the packaging of your dog foods: there’s no requirement for it.

For the most part, the source is more important than the amount provided that the fat and protein which is contained within the food is in order.

If you want an optimal source look for grain-free dog foods, particularly those which contain some fruits and leafy green vegetables. Berries and other “healthy” fruits are the best choice if you can find a food that contains them since they have the highest levels of antioxidants, phytochemicals, and micronutrients.

The Takeaway

Just a quick review before we move on:

  • Your dog’s ideal diet will be around 30%-35% protein and 25%-30% fat with the rest rounded out by fiber. Protein can be up to 45% or so without causing issues in most dogs.
  • The source of protein is super important, make sure you check the ingredients.
  • Omega-3 and Omega-6 fatty acids are essential for your dog’s health.
  • Carbohydrates can mostly be treated as a filler, but the source which they come from is super important.

Some Recommended Foods

While it’s impossible to identify just one food as the absolute best, especially since ideal macronutrient levels are still so contested, we recommend the following for each life stage of your animal.

Adult Dogs: Solid Gold Holistic High Protein Dog Food with Superfoods

For adult dogs, this high protein dog food is pretty much ideal although you may want to supplement with a little bit of extra fat. The ingredients are top-notch, however, and sure to contain plenty of micronutrients to keep your dog healthy.

For Puppies: Taste of the Wild Grain-Free Dry Dog Food for Puppy

This puppy food has a wide variety of protein sources to introduce a good array of amino acids and the carbohydrates contained within are all from great sources. A little bit expensive, but highly recommended.

For Elderly Dogs: Nulo Grain Free Senior Dog Food with Glucosamine and Chondroitin

For senior dogs, this food is an excellent option. The extra glucosamine helps to support ailing dog’s joints, which is a bonus for those animals who are beginning to experience the effects of old age in a serious way.

Related Reviews


Vitamins and minerals are considered micronutrients, since they don’t make up an appreciable amount of the bulk of your dog’s food.

However, these small amounts of chemicals make a huge difference in the health of your dog.

As a general rule, as long as you’re good about the ingredients contained within your dog food and your dog is healthy, your pet will be healthy. If you have to opt for cheaper food, or if your dog has some kind of health problem preventing proper metabolism of a nutrient, however, you’ll want to make sure that you supplement.

While it’s not quite as important to understand as macronutrients, understanding a little bit about vitamins and minerals can help you to make sure that you notice if any deficiencies happen.


Minerals are generally had in the form of inorganic salts, which really doesn’t mean much to most of us. The important part is that they’re present in the correct amounts since too much either way can end badly for your poor dog.

One of the worst offenders in this area is calcium.

Calcium is necessary for growing dogs, since it supports both their dentition and their bones as they get older but too much of it has the potential to cause skeletal abnormalities. This is particularly common in large dog breeds, so be careful not to over-do it if you’re supplementing.

The main culprit of low calcium is actually a 100% meat diet. Remember how we were saying that dogs are omnivorous?

Most foods are mineral supplemented so this isn’t a primary concern, but if you’re feeding a homemade diet then you’re going to want to ensure that there are vegetables in their diet as they’re the main source of minerals.

If you opt to do this, then you need to keep in mind that raw vegetables are harder to digest, but more nutrient dense, while the opposite is true if you lightly cook the vegetables. You can also put them in a blender and mix them in with the rest of the food you’re planning on feeding for a healthy compromise.

For the most part, mineral deficiencies will cause a dog to stop growing. If you notice that your dog has suddenly stopped gaining weight and size before their time, then you may want to take a closer look at their diet.


Just like their owners, dogs need to make sure that they get a good amount of vitamins. They come from diverse sources and aren’t supplemented in foods quite as often as minerals although even cheap foods will usually have some boost to their natural components.

The most studied deficiency in our canines is Vitamin A. It’s not likely to happen if you feed a good diet, since meat contains a good portion of it, but it can lead to motor and vision impairment, skin lesions, and all kinds of fun stuff.

Whereas minerals will often cause developmental difficulties, you’re going to be looking at some serious health problems emerging if a dog is vitamin deficient. Any kind of serious deficiency is likely going to require veterinary intervention but lethargy, losing hair, and skin problems are all likely signs that you may want to take a closer look at the diet.


There’s a pretty large market in dog supplements, and it’s ever growing as dogs aren’t quite adapted to the more laid-back modern life and people seem to think it’s a great way to help them lose weight instead of simply feeding less.

Even the lowest-quality dog food isn’t usually going to cause any kind of nutrient imbalance bad enough to require intervention. We don’t recommend supplementing vitamins and minerals unless your vet specifically tells you to do so. There are risks to some dogs and very little benefit to most.

However, there are some supplements which are quite useful.

Glucosamine-Chondroitin supplements are great for dogs who suffer from osteoarthritis. These compounds have been shown to increase mobility and reduce pain levels in suffering canines.

Fatty acid supplements have also been shown to improve hair and skin health for canines, and if you can afford them they’re generally a good idea for any dog who doesn’t have a compromised pancreas.

Other than those two, you should probably stick with what the vet recommends and always consult with them before you decide to land your dog on something. If you insist, herbs and amino acids are generally safe to utilize for your dog, but be extremely wary of supplementing vitamins or minerals without a vet’s direct recommendation.


We know this was a lot of information to take in, so let’s go over the most important points of dog nutrition one more time:

  • Macronutrient balance is probably the most essential part of your dog’s diet. At least 25% protein and 25% fat is ideal.
  • Protein sources are more important than the raw crude protein amount. Meat and eggs provide the most usable protein for your pet.
  • Carbohydrates are pretty much filler but the sources are important in making sure your dog gets their proper micronutrient balance.
  • Mineral deficiencies generally cause growth problems, serious vitamin deficiencies will present as health problems so watch your dog carefully.
  • Supplementing vitamins and minerals is risky, but fatty acids can help with their coat and skin while glucosamine is ideal for dogs with inflammation problems resulting from arthritis.
  • Most commercial foods use low-quality ingredients and a bad balance, which means you need to take your research very seriously if you’re looking to keep your dog in optimal health.

We hope that you’ve learned something from our guide, at the very least you can now know what you’re looking for when it comes time to do your own research on dog foods.



If you’re interested in the subject further, we recommend taking a look at any or all of the following:

Related Articles

Further Reading

  1. http://www.petmd.com/blogs/nutritionnuggets/jcoates/2013/aug/how-many-calories-does-dog-need-30849
  2. http://thebark.com/content/canine-nutrition-basics?page=2
  3. http://www.petmd.com/dog/nutrition/evr_dg_principles_of_dog_nutrition
  4. http://dels.nas.edu/resources/static-assets/banr/miscellaneous/dog_nutrition_final_fix.pdf
  5. https://www.aspca.org/pet-care/dog-care/dog-nutrition-tips
  6. http://www.dog-nutrition-naturally.com/canine-nutrition.html
  7. http://pets.thenest.com/ratio-meat-vegetables-grain-homemade-dog-food-11458.html
  8. https://trudog.com/many-calories-dog-really-need/


Susan Cropper

As a veterinarian practicing for 48 years, Dr. Cropper brings her priceless experience to all our readers. She is currently taking care of her two rescues, Ollie the Greyhound and Bryce the Pitbull mix, that is why she always sees things as a veterinarian and a pet owner simultaneously.

View all posts by Susan Cropper | DogsRecommend.com