Health and Nutrition

Risk of Obesity

– by Dr. Brian Laing

The Problem

  • Obesity is currently the most common nutritional disorder in pets.
  • In the U.S. 42% of dogs between the ages of 5-11 years are overweight.
  • Less than half the owners of overweight dogs recognise their dogs as being overweight.
  • Obesity is one of the easiest conditions for your Veterinarian to diagnose yet one of the most difficult to treat.
  • Allowing your dog to be overweight WILL decrease your pet’s lifespan!
  • Obesity has been proven to reduce the lifespan of dogs by almost 2 years.


The Science

A 2002 study1 followed 24 pairs of Labrador Retrievers throughout their entire lives. One group was fed ad libitum and the restricted group was fed 25% less. The calorie-restricted group lived an average of 13 years compared to 11.2 years for the ad libitum group.

This represents a difference in lifespan of 16%!

This is equivalent of a 75-year-old man living an extra 12 years!

Additionally, the ad libitum group suffered from an increased incidence of arthritis. Therefore the lives of the overweight dogs were not only shorter but more painful as well.

What is both surprising and troubling is that the Body Condition Score of 3.5/5 of the ad libitum group would not be classified as obese, merely overweight, yet the differences in quality of life and life span between the two groups were drastic.

Imagine what the results of the study would have been if it had compared an ideal body weight group of dogs to an obese body weight group of dogs.

Obesity is a chronic, low-grade inflammation affecting many body systems. This is because fat cells produce “fat-derived peptides” that are pro-inflammatory.

(The following from Small Animal Clinical Nutrition)

Another study2 showed that age related deterioration in immune function was slowed in dogs fed calorie-restricted diets, making them more resistant to disease.

Obesity is associated with increased risks of:

– Cancer
– Diabetes
– Urinary tract disease
– Liver disease
– Twice the risk of developing bladder stones
– Arthritis
– Ruptures knee ligaments
– Pancreatitis

Obesity is a Slippery Slope

Once a dog becomes obese it is harder for it to lose weight than it is for a thin dog to lose weight. This is because when a dog becomes obese, a number of genes change the way that they express themselves. The result is that fat cells start to produce a number of chemical hormones that have two important effects:

1. They stimulate the hunger centres
2. They lower the dog’s metabolism

This means that obese dogs are hit with the double whammy that they are hungrier than thin dogs, and that the amount of food appropriate for a thin dog of ideal weight will be 30-40% too much for that same dog if obese.

The Good News

Science has proven that we all have the ability to improve the quality of our dog’s lives while concurrently extending their lifespan simply by maintaining them in an ideal weight.

This App provides the tools to help you do just that.

In 2000 years science has verified for pets what Hippocrates had intuited for people so long ago:

“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.”

Factors that may increase your pet’s risk of developing obesity

  1. Basal Metabolic Rates
    – Basal Metabolic Rate (BMR) is the amount of daily energy expended by animals at rest
    – BMR is affected by body composition
    – The more lean muscle mass compared to fat a breed has, the higher the BMRFor example, Great Danes have a higher BMR than Labrador Retrievers, meaning that Labrador Retrievers are more prone to becoming obese than Great Danes.
  2. Neutering – Neutering decreases a dog’s energy expenditure by 20-30%.A study (Jeusette et al. 2004) showed that 2-year-old female beagles required a decrease of 30% in energy intake to maintain constant weight as compared to before spaying.
  3. Age – As many of us have discovered, we can’t eat the same amounts as we could when we were younger without gaining weight.

    The same sad fact holds true for dogs.

    Total daily energy needs of an average sized 7 year old dog decrease as much as 20% compared with its energy needs as a young adult.

  4. Breeds – Certain breeds are more prone to obesity than others.

    Breeds identified as prone to obesity are:

    – Labrador Retrievers
    – Golden Retrievers
    – Cairn Terriers
    – Cocker Spaniels
    – Long Haired Dachshund
    – Shetland Sheepdogs
    – Basset Hounds
    – Cavalier King Charles Spaniels
    – Pugs
    – Dalmatians
    – Beagles

    This is only a partial list. If your dog is not on the list, it is not a license to overfeed him/her.

    Any dog, if overfed on a regular basis, will become overweight.

Regardless of your dog’s inherent risk of becoming overweight, with the proper attention to his/her daily calorie intake, you can help your dog achieve and maintain an ideal weight and consequently live a longer and healthier life.

[1] Kealy RD, et al. J Am Vet Med Assoc. 2002;220:1315

[2] Greeley EH, Spitznagel E, Lawler DF, et al. Modulation of canine immunosenescence by life-long caloric restriction. Vet Immunol Immunopathol 2006;111:287-299.

About the Author: Dr. Brian Laing is a Veterinarian with 28 years of experience working in private practice. His passion in dealing with obesity in pets has led him to developing an App to help dog owners learn if their pet is overweight and calculate the proper amount of food to help reduce or maintain the pet’s ideal weight.
You can learn more about the App at:


Note: This section of the Canada’s Guide to Dogs website is intended as a source of information only. It is not intended as a substitute for professional care. Always consult with your Veterinarian about health related matters.

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