A new study by scientists at the University of Liverpool and Mars Petcare’s Waltham Centre for Pet Nutrition showed that the lifespans of overweight dogs were up to two-and-a-half years shorter than those of ideal-weight dogs.

50,000 dogs across 12 popular dogs breeds took part in the study. The deleterious effects of being overweight were observed across all 12 breeds, although the magnitude of the effects differed between breeds, ranging from a lifespan that was five months less for male German shepherd dogs to a lifespan that was two years and six months less for male Yorkshire terriers.

The findings indicate that overweight dogs are at increased risk of developing a range of chronic diseases, including orthopedic diseases, diabetes mellitus, and certain types of neoplasia. Metabolic derangements, functional impairment (most notably respiratory, cardiovascular, and renal function),and adverse effects on quality of life also occur.

The researchers stress that the study didn’t specifically examine the possible reasons for the dogs’ weight gain, such as overeating, because it was an observational study that didn’t look for cause.

NEWStat contacted corresponding author Alexander German, BVSc, PhD, CertSAM, DECVIM-CA, MRCVS, professor of small-animal medicine at the University of Liverpool’s Institute of Veterinary Science, to get his perspective.

NEWStat: Are dog owners generally aware if their dogs are overweight?

Alexander German: A number of other studies, including our own, have indeed indicated that owners underestimate the weight status of their pet. The effect is more pronounced in dogs than in cats, but exists nonetheless. That said, a reasonable suggestion for the veterinary profession would be to focus more on awareness of obesity and body condition. Veterinary professionals would probably find it easier to introduce the topic of obesity if they discussed body shape and what constitutes a healthy shape first. It can then be easier to relate this to a dog’s or cat’s current [body condition score], thereby avoiding the need to use the “f” word (fat) or the “o” word (obese), given their negative connotations.

NEWStat: Although the study doesn’t specifically address what causes obesity in dogs, overeating is clearly a possible culprit. What can veterinarians do to encourage their clients to feed their pets healthier portions?

AG: The key areas to discuss would be: awareness of the calorie content of the food, awareness of the typical maintenance-energy requirement for a typical dog or cat of that size (as well as age, sex, and neuter status), and the need to measure out portions accurately. We recommend avoiding the use of measuring cups, which we have found to be imprecise and inaccurate [and lead] to overfeeding about 80% of the time. Instead, portions are better weighed out using electronic gram scales. In addition, vets should not be afraid to advise on diets and sell them if they wish to.

NEWStat: If the veterinary profession continues its move toward officially classifying obesity as a disease, how might that affect the way we approach the treatment of overweight dogs?

AG: I am strongly in favor of classifying obesity as a disease and [I] was one of the authors of the position statement of the Global Pet Obesity Initiative. We now have 23 veterinary organizations and allied associations who have endorsed the statement, so we are very much heading toward a consensus on this. [AAHA’s Board of Directors endorsed the position statement in April 2018.]

The reason I favor classifying obesity as a disease is that the scientific evidence supports this classification, not just in people but also in pets. Of course, I am a realist, and I don’t believe that this single step will cure obesity. However, I hope that it would start to shift the narrative, not just within the veterinary profession but also in wider society.

By changing the narrative about obesity, I am hopeful that it will encourage more veterinary professionals to hold [supportive, nonstigmatizing] conversations about obesity with pet owners.

Read the 2014 AAHA Weight Management Guidelines for Dogs and Cats here.

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