Older Dogs Often Need Fewer Calories

As dogs age, many become less active. They may take shorter walks, sleep more and burn fewer calories throughout the day.

A National Academies guide based on the report Nutrient Requirements of Dogs and Cats states that older dogs may need about 20 percent fewer total calories than middle-aged adult dogs because of decreased physical activity and a slower metabolism.¹

That is a general estimate, not a feeding rule for every older dog. Breed, size, activity, body condition, health and individual metabolism all matter.

Continuing to provide the same number of calories after a dog's activity declines can lead to weight gain. That extra weight places more pressure on aging joints and can make movement even harder.

The goal is not to underfeed the dog. The goal is to provide enough nutrition without supplying more energy than the dog uses.

Fewer Calories Does Not Mean Less Protein

Protein supplies amino acids the body uses to maintain muscle, repair tissue, produce enzymes and support many other biological functions.

The National Academies guide states that older dogs appear to require somewhat more protein to maintain their protein reserves, possibly as much as 50 percent more than younger adult dogs.¹

That does not mean every senior dog should immediately be fed 50 percent more protein. It means that age alone is not a sound reason to restrict protein.

A review of dietary protein in dogs reached a similar conclusion. It reported that protein restriction is unnecessary for healthy older dogs and may be detrimental, especially when their calorie needs are also declining.²

Muscle Loss Can Hide Behind a Normal Weight

Older dogs are vulnerable to age-related muscle loss, sometimes called sarcopenia.

A dog can remain close to the same weight while its body composition changes. Muscle may decrease while body fat increases. Looking only at the number on the scale can cause that muscle loss to be missed.

Research comparing healthy younger and older dogs has found measurable differences in muscle mass, even among dogs with similar body-condition scores.³

This is why an older dog's muscle condition should be evaluated separately from its weight. An overweight dog can still be losing muscle.

Why Simply Feeding Less Can Backfire

Suppose a dog begins gaining weight, so the owner cuts the food portion by 25 percent.

That reduces calories, but it also reduces everything else in the bowl, including:

• Protein and essential amino acids
• Essential fatty acids
• Vitamins
• Minerals

If the food is already relatively low in protein, substantially reducing the portion may make it harder for the dog to receive enough protein while staying within its calorie allowance.

That question can be more useful than looking only at the crude protein percentage on the bag.

A healthy senior dog with declining calorie needs may benefit from a diet that provides a stronger protein-to-calorie ratio. This allows calories to be controlled without unnecessarily reducing the protein available to support lean muscle.⁴

Protein Quality Matters Too

The crude protein number does not tell the entire story.

Dogs require specific essential amino acids. The protein in a diet must be digestible and provide an appropriate amino-acid balance for the body to use it effectively.

Two foods can show the same crude protein percentage while providing different protein sources, digestibility and amino-acid profiles.

Higher is not automatically better, but lower is not automatically safer. The complete formulation, calorie density, digestibility and amount actually being fed all matter.

What About Kidney Disease?

This is where the subject often becomes confused.

Being old is not the same as having kidney disease.

A healthy senior dog should not automatically be placed on a protein-restricted diet simply because of age.

A dog with diagnosed chronic kidney disease is a different situation. Dietary decisions may depend on the stage of disease, phosphorus level, urine protein, blood pressure, appetite, body weight, muscle condition and other diagnostic findings.

The International Renal Interest Society recommends diagnosing and staging chronic kidney disease using the dog's full clinical and diagnostic picture. Staging commonly includes creatinine or SDMA, along with assessment of blood pressure and protein in the urine.⁵

A kidney diet is not simply a low-protein diet. These diets typically adjust several nutrients, with phosphorus management playing an especially important role.

Medical nutrition decisions should be based on actual test results and the individual dog, not the dog's birthday or one isolated blood value.

Look at the Dog, Not Just the Birthday

There is no single age when every dog becomes nutritionally senior.

A large or giant-breed dog may show age-related changes earlier than a small dog. One 10-year-old dog may still be active and muscular, while another may have arthritis, dental problems, kidney disease or significant muscle loss.

When evaluating an older dog, pay attention to:

• Whether the ribs can be felt without pressing hard
• Whether a waist is visible when viewed from above
• Whether the hips, spine or shoulders are becoming more prominent
• Whether the rear legs are losing muscle
• Whether the dog is gaining fat while becoming weaker
• Whether appetite, thirst, urination or mobility has changed

Body condition and muscle condition should be evaluated separately. The scale tells only part of the story.

A gray muzzle is a stage of life. It is not a diagnosis.