Updated: Apr 8, 2021
Please have discussions with your veterinarian about any nutrition information you read, including this page. This information is not meant as medical advice for your dog but is instead of set of general guidelines that can typically be used along with common sense for the average dog.
A great source to read intelligent articles about new research and annual dog food reviews is Whole Dog Journal, accessible by subscription or online. Many online blogs and articles are full of sensational information that may be inaccurate or simply outdated, so always discuss information with your veterinarian.
The aisles at the pet store have never been filled with more options for feeding your puppy. Don’t get taken in by marketing hype, though. Research is available and ratings are available at sites like DogFoodAdvisor.com if you want to learn more. I would not tend to make decisions based on their ratings as the site is not run by a vet or vet nutritionist; I would use it to check ingredients and calorie content and it's a great place to hear about recalls.
Here is some basic info to get you started in choosing a good brand. A great book with very detailed info is Dog Food Logic by Linda Case. The recommendations below are general, taken from that book, and meant to serve as information to discuss with your vet. Dogs with allergies or other medical conditions may require special diets, not discussed here.
Dogs are omnivores, so they can eat meat and grain, and excellent scavengers, as you will notice if you leave a sandwich on the counter!. Common allergens are beef, dairy, soy, and, less commonly, corn or wheat. You may even see your puppy eat grass or plants which is totally normal and is not associated with illness or nutrient deficiency. Be sure you don't have any poisonous plants in your yard, though!
A dry food at contains between 3 and 7% fiber is normal and beneficial. Including protein sources like salmon, herring, and white fish provides beneficial fatty acids and is considered superior to fatty acids derived from flax, flaxseed, and canola oil. A good ratio of omega 6 fatty acids to omega 3 fatty acids is between 7:1 and 5:1.
Protein sources are whole meats or meat meals or by-product meals. When whole meat is included, a high proportion of water is cooked off during processing and contributes just a small amount of protein, so it’s common to see a meat meal on the ingredient list, too. As a result, that second ingredient on the list is usually the primary protein source, so be sure to read it and be sure the first 2 ingredients are a meat and a meat meal. (By-product meals are typically lower quality.) The remaining ingredients should be grain, fruit, vegetable, vitamin, and mineral. If you don't recognize an ingredient, it's likely what we could consider a "filler." If corn is included as the grain ingredient, I find that the dog often has more bowel movements as corn is just fiber without nutrition.
A growing puppy needs about twice the number of calories per day as an adult who weighs the same and need a higher proportion of protein than adults, about 22% of their diet. So, decrease calories when your dog reaches adult size or as indicated by your vet. That’s about 6 months old for small breeds and 8-10 months for larger dogs.
Large breed puppies are susceptible to skeletal disorders such as hip and elbow dysplasia due to rapid growth and large adult size. You should be careful to feed a large breed puppy food to these pups because it will limit calcium and calories to help avoid an increased risk of skeletal disease. Be careful to keep them fairly lean, too. If someone tells you to feed adult food instead, do not take that advice; many people and even breeders make this recommendation without having studied the research which is available from Cornell University, if you are interested.