Overweight and obesity are among the most common conditions veterinarians see in both dogs and cats.

Yet weight-loss plans for pets are frequently unsuccessful, with a high drop-out rate. In one study, over half of participating dogs actually gained weight.

In a new study published in the journal Animals, we argue weight management in pets often fails because we view it too narrowly – as a nutritional problem that can be solved simply by feeding the animals less.

Yet evidence suggests to manage weight in pets, we also need to attend to animal behaviour, and human-animal interactions are a huge part of that.

How do I know if my pet is overweight or obese?

Body condition scoring is the most common method vets use to classify animals as underweight, ideal weight or overweight.

The Global Pet Obesity Initiative uses a scale of 1–9, with a body condition score of 5 representing ideal body weight.

Each category between 1–9 represents a 10% difference in weight. For example, an animal with a body condition score of 6 out of 9 is 10% overweight, while a score of 7 out of 9 means the pet is 20% overweight. Obesity is defined as having a body condition score of 8 out of 9 (30% overweight) or above.

How common are overweight and obesity in pets?

Globally, about half of the pet dog and cat population is overweight or obese, with middle-aged pets most commonly affected.

The largest study (conducted in the United States), comprising almost 5 million dogs and more than 1 million cats,........

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