Nutrition and Your Senior Dog’s Body

In the past, dietary recommendations for senior dogs have largely been drawn from nutritional management of diseases common to the aging process. Research, however, has shown that special nutrition can proactively help manage body-condition problems common in aging dogs, such as the obesity and loss of muscle mass. Senior dogs also benefit from special nutrition to help maintain bone and joint health.


Senior dogs tend to gain weight, despite consuming fewer calories, either due to changes in their metabolic rate. They, therefore, benefit from eating a diet with reduced fat levels and lower caloric density than adult maintenance foods.

Recent IAMS research in dogs also indicates that L-carnitine—a vitamin-like compound made in the body from the amino acids found in red meats, fish, chicken, and milk—can help reduce weight in overweight dogs by escorting fat into cellular mitochondria where it is turned into energy.

Loss of Muscle Mass

Protein is the building block of muscle tissues. It is important for maintenance of muscle tissues, muscle strength, and mobility. Recent research conducted by The IAMS® Company has shown that senior dogs who eat a higher-protein diet better maintain muscle protein stores. By providing optimal protein levels from muscle maintenance, we can allow senior dogs to continue being physically active.

This research is contrary to conventional opinion that senior dog foods should contain lower protein levels than adult maintenance formulas in order to avoid progressive decrease in kidney function. However, senior dogs that were fed a high-protein diet had stable renal function and a lower death rate than those dogs fed a lower-protein diet.*

Maintaining Bone and Joint Health for Senior Dogs

During the aging process, cartilage between joints often begins deteriorating. There are several ways in which nutritional management might help maintain healthy bones and joints and mobility in dogs.

  • Glucosamine and chondroitin sulfate are naturally occurring compounds that aid in the nourishment and maintenance of healthy joint cartilage. They aid in building strong cartilage and ensuring joint lubrication.
  • Optimal levels of vitamins and minerals promote the efficient production of cartilage, and nutritionally support bone and nerve function.
  • A complete and balanced diet with an adjusted omega-6:omega-3 fatty acid ratio nutritionally supports the natural healing process.


Some pet-food manufacturers have endorsed reduced levels of calcium and phosphorus based on the belief that excesses of these minerals are harmful to the kidneys. However, research has shown that no damaging accumulation of calcium or phosphorus was found in the kidneys of older dogs fed diets containing maintenance levels of calcium and phosphorus for four years.*

* Finco, DR. “Effects of aging and dietary protein intake of uninephrectomized geriatric dogs.” American Journal of Veterinary Research; Vol. 55, No. 9. Sept. 1994.