How to Feed Dogs in Different Life Stages (Based on Scientific Research)

As the dog ages, her nutritional requirements will change for a variety of reasons, most commonly due to energy expenditure and metabolism, and deteriorating health condition.

Despite what you see on dog food packages, there isn’t one best dog food that fits all the various nutritional needs of dogs of all ages. Current research supports the suggestion that as dogs grow in size and their body ages, their requirements for vitamins, minerals and nutrients change.

The dog food industry has taken note of this and started to provide diets tailored to meet the various nutritional needs of dogs’ life stages. Choosing a diet tailored to your dog’s age is an important way to maintain good health.

This article explores the dog food choices available for various life stages in dogs.

“All Life Stages” Diets

There are diets marketed to be adequate for all life stages; however, this needs to be carefully considered prior to feeding (1).

The term “All Life Stages” includes growing puppies, working dogs, sedentary dogs, senior dogs, and pregnant and nursing dogs. Obviously these animals will have different nutrient needs and a ‘one size fits all’ diet won’t work for all.

“All Life Stages” diets tend to be higher in calories than a diet aimed for solely adult dogs, such as an adult maintenance diet, and dogs with decreased energy requirements can become predisposed to obesity.

In addition, these diets have too much calcium per energy provided for growing puppies. This is especially true for giant or large breeds, such as Great Danes, Mastiffs and Rottweilers, which opens them up to risks of various developmental diseases (2).

An “All Life Stages” diet may be an appropriate choice for a dog whose nutritional needs are not complex, such as a very active young medium sized adult dog. However, exercise caution when feeding an “All Life Stages” diet to older pets with decreased calorie needs, and it’s best to avoid it for growing puppies.

Summary: “All Life Stages” diets are not appropriate for majority of dogs, particularly puppies, and some adult and senior dogs. They’re higher in caloric content and will likely be suitable only for very active or working dogs.

Growth Foods (for Puppies)

One of the most nutritionally demanding times in a dog’s life is the first year or so of the puppy’s life. Dogs grow much more quickly than people, often reaching full growth potential in just one to one and half year period (3, 4).

Feeding a diet designed specifically for puppies is crucial during this time of rapid growth to prevent the development of orthopedic diseases, such as hip dysplasia and Osteochondritis dissecans.

It is generally recommended that young dogs stay on puppy food until they are about 80% full grown to help prevent this. Small and medium breed dogs may reach close to their adult size well before a year, whereas large breed dogs may continue to grow beyond a year of age and reach skeletal maturity around 15-18 months of age.

Diets labeled for growth (i.e. puppy food) are different from other diets in that they have less calcium and a narrower ratio of calcium to phosphorus. There are many puppy diets designed specifically for growth (e.g. Purina ProPlan Puppy, Science Diet Puppy, Natural Balance Puppy, and IAMS Puppy, etc.)

The demand for nutrition in the form of calories is extremely high during this time (5). Many dogs have most of their growth potential in the first year. Some breeds are expected to weigh over 100 pounds by this time. The amount of calories needed to sustain this rapid growth is extensive.

Especially large and giant breed puppies (those expected to grow larger than 70 pounds at full maturity), will become more predisposed to devastating orthopedic diseases when their diet is not specifically designed for growth (6, 7, 8, 9, 10).

The improper ratio of calcium and phosphorus can disrupt bone development and too much calcium can cause too rapid bone development, both of which can lead to orthopedic issues.

The AAFCO (Association of American Feed Control Officials) recently started requiring specific pet food labels for large and giant breed puppy food, and manufacturers are expected to comply with these new guidelines this year.

It’s generally not recommended to feed puppies homemade dog food due to how difficult it is to include all the nutrition and ensure proper balance. There are many cases of puppies experiencing severe nutrient deficiencies due to improperly balanced home foods.

How much to feed a puppy

One of the more challenging aspects of puppy nutrition is knowing how much to feed. Every puppy will be different; even those from the same litter may have different calorie needs based on their activity level and their growth potential.

The most important aspect of feeding a puppy is to ensure they are not overfed, because it can lead to obesity. Generally, a puppy that starts out overweight is predisposed to obesity for the rest of his life. Since obesity is a major health concern for dogs, the right diet from the get go is crucial.

Veterinary nutritionists will recommend that new puppy owners learn to ‘lean feed’ their puppies. What this means is that you, the owner, learn to be very familiar with how your puppy’s body looks and feels.

If the puppy is starting to grow out rather than up, you need to cut back. But if the ribs are more prominent than normal, then it’s time to increase how much you are feeding.

The easiest way to avoid overfeeding or underfeeding, as well as prevent a number of diet related diseases in dogs, is to learn about the Body Condition Scoring (BCS) table and guidelines, posted below. Download our full BCS chart here (PDF).

Dog Body Condition Scoring (BCS) Chart

Moreover, read the study guidelines from any reputable sources, like these two:

The dog’s BCS should be reassessed after any major age/disease related surgeries and after spaying/neutering, at which point the calories need to be dropped by approx. 30% to account for lower energy requirements (11).

Summary: The best diet for a puppy is a diet labeled for growth. This is especially important in larger breeds. While the amount of food needed will vary from dog to dog, learning to ‘lean feed’ will help create a healthy weight for the rest of his life.

Maintenance Foods (for Adult Dogs)

Feeding a diet designed for adult maintenance will help ensure your dog receives the necessary nutrients and maintains a proper weight once the dog has reached his full growth potential.

Adult dogs of the same size can have vastly different calorie needs, thus selecting a diet with the proper calorie density is important (12). Calorie needs are dependent on age, body size, activity level and whether or not the dog is spayed or neutered (13).

For example, working dogs, or very active dogs, will do better on an adult food with a higher calorie content, whereas more sedentary dogs may benefit from a less calorie rich diet labeled “Lite”, or “Weight Control” (14).

In general, diets labeled “Lite” or “Weight Control” have been formulated to help dogs feel more full and have been designed to have less calories overall per kibble to help encourage weight loss or weight control. These diets would not be appropriate for active dogs needing a lot of calories, or for growing puppies.

Maintaining a lean body composition despite what is being fed is likely the biggest contributing factor to overall health for adult dogs. Studies show that extra weight in the form of fat increases the body’s level of inflammation leading to a variety of diseases, in addition to creating more strain on joints and the heart (15, 16, 17).

Seeking out specific adult dog food recipes is generally not as important as ensuring the calorie amount you are feeding doesn’t lead to obesity. There are many reputable brands available that will provide all the essential nutrients your dog needs.

Summary: Choose a type of food that fits your dog’s lifestyle and count his calories. A “Lite” diet will be more appropriate for dogs that tend to be heavy, and an “Active” or “Working Dog” diet will be more appropriate for dogs with higher energy expenditure.

Geriatric Foods (for Senior Dogs)

As dogs reach their older years, their nutritional needs change. Older pets are more prone to a variety of different ailments, including kidney dysfunction, arthritis and cognitive changes, to name a few (18, 19, 20, 21).

Different breeds of dogs reach ‘senior’ status at different times, and the timing for switching to a senior formula will vary. Large and giant breeds will reach their senior years much more quickly than smaller toy breeds (22).

For example, many veterinarians will consider a six to seven year old Great Dane a ‘senior’, but likely wouldn’t classify a Chihuahua as a senior until she reaches closer to nine or ten years of age.

The AAFCO doesn’t recognize the term “Senior” diet, therefore, there is no standard or requirement for companies how to label dog food for senior dogs. Most diets labeled for seniors will vary widely (23). In addition, there is little research that has outlined the optimal nutrient profile for older pets. Thus many companies define their own idea of what’s best for senior dogs.

Keeping this variation in mind, senior dogs will often do just fine on adult dog food. In fact, if your dog has been healthy and well maintained on a regular adult food all of her life, switching is probably not necessary.

In general, senior dog food brands tend to have less fat to help prevent obesity, and moderate protein levels to help preserve muscle mass, while decreasing the workload required by the kidneys.

It is important to understand that it isn’t necessarily fat content in diets by itself that causes obesity in dogs. Obesity is simply caused by over-consumption of calories, whether in the form of fat, protein or carbohydrates (24, 25).

Senior dog food diets may contain increased levels of antioxidants. It has been shown that certain antioxidants help slow down brain aging and prevent cognitive changes in senior canines (26, 27, 28). This research suggests that antioxidants help decrease levels of free radicals which can damage cells and cause aging.

Many senior dog food formulas will also contain glucosamine (and sometimes chondroitin and/or MSM) aimed at supporting joint health of aging dogs. There’s some research that supports this (29, 30).

However, while the theory is sound, the amount needed to be therapeutic for an aging dog is lacking in any currently existing dog food recipe. A separate glucosamine supplement will be more effective than relying on the amounts found in senior diets (31).

If your older dog has a specific disease process, such as kidney disease, then a prescription diet specially formulated for that illness is likely to be most beneficial (32). These diets are available only from a veterinary hospital under the supervision of a veterinarian.

The diets are prescription-only because they are not appropriate for all dogs, and most of the diseases being treated with prescription diets will require veterinary monitoring.

Aging dogs are more prone to a variety of health problems. As these disease processes develop, work with your veterinarian to add on specific supplements or prescription dog food diets that will keep your senior dog healthy.

Summary: As the dog reaches senior years, nutrition is key. But you don’t have to rush and change what you’re feeding. Tailoring the amount of current dog food to adjust to your dog’s declining activity level and decreased metabolism will help keep her lean. For any specific disease, discuss any adjustments and/or prescription diet with your vet.

Take Home Message

It is important to recognize that dogs’ nutritional needs change over time. Being familiar with how diets vary depending on life stages can guide pet owners to selecting the most appropriate type of dog food.

That said, do not buy into the marketing terms. There are only a few general types of dog food you must be aware of – growth and maintenance in particular – to keep your dog healthy. Keep an eye on your dog’s caloric intake and adjust accordingly.

“All Life Stages” diets are not ideal for puppies. Formulas like “Active” are perfect for working dogs or those that expend more energy on a daily basis. “Weight Control” diets are good for sedentary or obese pets.